HOT MIX ASPHALT, TROUBLE SHOOTING, PROCESS CONTROL (HMA-TPC)

Transcription

1 HOT MIX ASPHALT, TROUBLE SHOOTING, PROCESS CONTROL (HMA-TPC) HIGHWAY TECHNICIAN CERTIFICATION PROGRAM University of Wisconsin-Platteville 049 Ottensman Hall 1 University Plaza Platteville WI Office phone: Fax: follow us on

2 PREFACE Intro - 1 The Hot Mix Asphalt Troubleshooting & Process Control training course was developed as a team effort with cooperation from the Wisconsin Department of Transportation and the asphalt highway construction industries. The following committee members and class instructors have been very instrumental, along with many others, as contributors in developing the content of this course manual: Judie Ryan, Consultant Brian Pitlik, Pitlik & Wick, Inc. Lance Mangles, Pitlik & Wick, Inc. Joe Kyle, American Asphalt of WI. Karl Runstrom, Northeast Asphalt John Jorgenson, Mathy Construction Pat Shuda, WisDOT North Central Region Jeff Merten, UW-Platteville Aaron Coenen, Truax Center Madison, WI WisDOT Technical Assistance Hotline Representative Barry Paye, WisDOT Bureau of Technical Services, WisDOT Technical Hot-Line Representatives SW Matt.Smith@dot.wi.gov Madison Matt Smith SW Steven.Ames@dot.wi.gov LaCrosse Steve Ames SE Waukesha Jim Boggs NE Green Bay Brian Jandrin NC WI Rapids NC Rhinelander NW Amber.Bever@dot.wi.gov Eau Claire Amber Bever NW Thomas.Rossmann@dot.wi.gov Superior Tom Rossman BTS Jeffrey.Anderson@dot.wi.gov Madison Jeffrey Anderson

3 TABLE OF CONTENTS Intro - 2 Course Overview Introduction Course Prerequisites Certification Requirements Recertification Requirements Revocation/Suspension of Certification Highway Technician Certification Program Goal Course Syllabus Topic A Course Introduction Welcome... A-1 Introduction of Course Participants... A-1 What Do You Expect From This Training Course?... A-1 Duties and Responsibilities of a HMA-TPC... A-1 Comprehensive Survey... A-2 Acronyms for Asphalt... A-3 Topic B Quality Management Program What is Quality Management... B-1 WisDOT Quality Management Program, Standard Specification Section 460 WisDOT Construction and Materials Manual Section 8-36 Exercises... B-2 Topic C Overview of Mix Design Purpose of Asphalt Mix Design... C-1 Laboratory Design versus Field Production... C-1 Asphaltic Mix Design Report and Job Mix Formula... C-1 Asphalt Mix Design Report... C-4 Maximum Density Line Relationships... C-5 VMA, Voids in the Mineral Aggregate... C-6 Test Property Curves for HMA... C-9 Selection of Percent Asphalt Content from Air Voids Data... C-10 Selection of Percent Asphalt Content Satisfying All Design Criteria... C-10 Dust to Binder Ratio... C-11 Increase of P-200 During Mix Design... C-11 Asphaltic Mix Design Review Process... C-12 Mix Design Exercises... C-13 Topic D Aggregate Blending

4 Intro - 3 Aggregate Blending... D-1 Federal Highway Administration (FHWA) 0.45 Power Chart... D-6 Maximum Density Line... D-6 Aggregate Blending Exercises... D-8 Topic E Quality Control Organizational Plan Quality Control Organizational Plan... E-1 Request for Job Mix Formula Change... E-6 Job Mix Formula Adjustment... E-6 Quality Management Process Flow... E-8 Asphaltic Mixture Sampling Plan... E-8 Random Sampling Exercises... E-9 Topic F CMM and Standard Specifications CMM F-1 CMM F-2 SS F-15 Topic G Asphalt Mixing Plants Asphalt Mixing Plants... G-1 Exercises on Asphalt Mixing Facilities... G-2 Topic H Process Control of Asphaltic Mixtures Process Control of Asphaltic Mixtures... H-1 Aggregate Gradation... H-1 Stockpile versus Cold Feed Gradation Data... H-1 Cold Feed versus Extraction Gradation Data... H-1 Asphalt Content... H-2 Nuclear Gauge... H-2 Significance of Gradation and Asphalt Content... H-3 Sources of Possible Problems in a B.M.F.... H-6 Sources of Possible Problems in a Drum Plant... H-7 Problems Associated with Aggregate... H-9 Factors or Causes Attributed to Aggregate Problems... H-10 Factors Attributed to Production (Plant) Problems... H-10 Causes Attributed to Production (Plant) Problems... H-11 Factors Attributed to Equipment-Related Problems... H-12 Aggregate Diagnostic Problems... H-13

5 Intro - 4 Gradation Variability... H-14 Mixture Diagnostic Problems... H-15 Change in Maximum Specific Gravity, Gmb Indicates... H-15 Process Control Problem Solving Using a Flow Chart... H-16 Exercises on Asphalt Mixing Facility... H-17 Topic I Troubleshooting Mixtures, Sampling and Testing, and Asphalt Problems Sampling and Testing Errors in Aggregate... I-1 Sampling and Testing Problems Associated With Asphaltic Mixtures......I-2 Factors Affecting Maximum Specific Gravity, Gmm... I-3 Exceeding Allowable Differences on Test Results... I-3 Calculations Using Theoretical Maximum Specific Gravity, Gmm... I-4 Topic J Process Control Relationships Control Charts... J-1 Gradation Master Band... J-1 Documentation... J-2 Relationships of Asphaltic Mixture Properties... J-2 Asphaltic Mixture Property General Guidelines... J-4 Predetermined Proportionality Rules for Asphalt Mixture Properties J-4 Process Control Relationship Exercises... J-5 to J-15 Topic K Process Control Relationship Problems APPENDIX Appendix 1: Answers to Student Problems, Mechanics of Mix Design & Recycling Appendix 2: QMP Award, Corrections, Course Evaluation

6 Course Overview Intro - 5 Introduction The Highway Technician Certification Program (HTCP) welcomes you to the Certified Asphaltic Technician TPC course. This course requires 20 hours of classroom attendance. The course content will cover Wisconsin Department of Transportation (WisDOT) standard part 4 specifications related to asphaltic pavements, aggregate blending, guide for quality management program activities, hot mix asphalt design methodology; types of asphalt plants, process control/troubleshooting techniques, and statistical quality control. Course Prerequisites Student candidates must have successfully completed one construction season of field experience in materials testing after certification as a Certified Asphaltic Technician IPT (including all prerequisites). A person may earn 2.0 continuing education units (CEUs) upon successful completion of this course. Certification Requirements The written examination will be limited to a maximum duration of two (2) hours. The written examination will be open book and open notes and will consist of true/false questions, multiple choice questions and essay problems. A student will be required to obtain a passing score of 70 percent to be certified as an Asphaltic Technician TPC. Recertification Requirements Recertification is mandatory every three (3) years. The HTCP will send a recertification notice to each certified technician and the firm or agency prior to the expiration date of the highest certification level(s) of certification obtained. The certified technician must apply for recertification before the expiration date of the highest level(s) obtained. Each certified technician is responsible for obtaining his/her recertification. Recertification may be obtained in one of the following ways: Complete the next level certification course: A certified technician can obtain recertification by enrolling and successfully completing the next level certification course. Comprehensive Recertification Exam: Technician can attend the last day of any relevant certification course offered on the course schedule and take the comprehensive recertification exam or come to a remote comprehensive site held throughout the state. Class at a reduced fee: Opportunity to come back through classroom training to recertify at a reduced fee. A person may earn 2.0 Continuing Education Units (CEUs) upon successful completion of this course.

7 Intro - 6 Revocation/Suspension of Certification Upon written request from any individual, firm, agency, or contractor associated with the HTCP, the HTCP director will provide technical assistance in investigating any alleged report(s) of either certified technician incompetence or act(s) of malfeasance. The HTCP director will then notify WisDOT of the report findings concerning certified technician incompetence or misconduct. Highway Technician Certification Program Goal The principle goal of the Highway Technician Certification Program (HTCP) is to certify that individuals have demonstrated the abilities to engage in quality control/quality assurance activities in highway work contracted by the Wisconsin Department of Transportation (WisDOT).

8 Intro - 7 Course Syllabus 8:00-8:15 COURSE OVERVIEW Day 1 8:15-9:00 TOPIC A: Course Introduction 9:00-11:00 TOPIC B: Specifications a. WisDOT QC/QA 11:00 - NOON TOPIC C: Overview of Mix Design a. Method b. Report. NOON - 1:00 LUNCH BREAK 1:00-1:30 TOPIC D: Aggregate Blending 1:30-2:30 TOPIC E: Q.M.P. Guide/Procedures/Verification Guidelines Outline 2:00-3:30 TOPIC F: Q.M.P. Activities 3:30-4:30 TOPIC G: Plant Operation-Reference part II in U.S. Army Corps Handbook Hot-Mix Asphalt Paving a. Batch b. Drum 4:30-5:00 TOPIC H: Process Control - Mix Design Property Problems (What) a. Gradation b. Voids c. VMA d. % AC Day 2 8:00-9:30 TOPIC I: Process Control - Problem Causes (Why) a. Materials b. Manufacturing Process c. Test Methods 9:30 - NOON TOPIC J: Process Control - Problem Solutions (How) a. Materials (Blending/Handling) b. Manufacturing Process (Plant Calibration Operation) c. Test Methods (Calibration/Calculations) NOON - 1:00 LUNCH BREAK 2:30-5:00 TOPIC K: Asphaltic Mix Design Troubleshooting Exercises Day 3 8:00-9:00 TOPIC K: Asphaltic Mix Design Troubleshooting Exercises (Continued) 9:00-10:00 General Review 10:00 - NOON Written Examination and Course Evaluation ADJOURN

9 TOPIC A: Course Introduction

10 TOPIC A: Introduction Page A-1 WELCOME! The HTCP welcomes you to the Hot Mix Asphalt Troubleshooting & Process Control training course. First of all, please make sure you have satisfied all course prerequisites before completing this course. Certification will be granted only if you successfully complete this course and have satisfied all course prerequisites. Introduction of Course Participants As a Hot Mix Asphalt IPT Process Control Technician, you have gained valuable work experience by testing the overall quality of asphalt paving mixtures. The intent of this course is for the participants to have an opportunity to gain a wealth of knowledge by sharing their work experiences with others. At this time, you will be asked to introduce yourself, company name, years of service to the asphalt industry, and your present occupational duty. What Do You Expect From This Training Course? This is your opportunity, as a course participant, to ask the course instructor to cover any other topics related to asphalt paving mixtures. Please list and identify any additional related asphalt paving mixture topics below: Duties and Responsibilities of a Hot Mix Asphalt Troubleshooting & Process Control Technician: The duties and responsibilities of a Hot Mix Asphalt Troubleshooting & Process Control Technician involve: Knowing which samples and tests are required, being able to perform them, and computing the test data results Knowing who is responsible for sampling and testing asphalt

11 TOPIC A: Introduction Page A-2 Knowing the proper frequency of sampling and testing and being able to sample and test as required by specification Knowing the mathematical random number process for selecting a sample location and when it is required by specification Knowing the specification requirements and evaluating test results in relation to these specifications Being able to properly prepare, maintain and analyze control charts and controlling the production process by making troubleshooting adjustments that comply with the asphaltic mixture specifications Being able to maintain records in an organized manner and documenting sampling and testing performed and actions taken as a result of sampling and testing required by specification

12 TOPIC A: Introduction Page A-3 Acronyms for Asphalt Acronyms Pertaining to Hot-Mix Asphalt AASHTO AC AMRL ASTM CA CAA ESAL FAA G b G mb G mm G sa G sb G se HMA JMF MEPDG NAPA NCAT NCHRP NMAS P b P be P ba P s QC QMP QV RAM RAP RAS SGC SHA SHRP SMA SSD TSR VFA VFB VMA VTM or VA WAPA WHRP WMA American Association of State Highway & Transportation Officials Asphalt Cement (Liquid Binder) AASHTO Materials Research Laboratory American Society for Testing & Materials Contractor Assurance Coarse Aggregate Angularity Equivalent Single Axle Load Fine Aggregate Angularity Specific Gravity of the Binder Bulk Specific Gravity (Asphaltic Mixture) Maximum Specific Gravity of the Mixture Apparent Specific Gravity (Aggregate) Bulk Specific Gravity (Aggregate) Effective Specific Gravity (Aggregate) Hot-Mix Asphalt Job Mix Formula Mechanistic and Empirical Pavement Design Guide National Asphalt Pavement Association National Center for Asphalt Technology National Cooperative Highway Research Program Nominal Maximum Aggregate Size % Binder Effective % Binder % Binder Absorption % Stone Quality Control Quality Management Program Quality Verification Recycled Asphalt Materials Recycled Asphalt Pavement Recycled Asphalt Shingles Superpave (or SHRP) Gyratory Compactor State Highway Agency Strategic Highway Research Program Stone Matrix Asphalt Surface Saturated Dry Tensile Strength Ratio Voids Filled with Asphalt Voids Filled with Binder Voids in Mineral Aggregate Voids in Total Mix (Air Voids) Wisconsin Asphalt Pavement Association Wisconsin Highway Research Program Warm Mix Asphalt

13 TOPIC B: Quality Management Program

14 TOPIC B: Specifications and Construction and Materials Manual Page B-1 What is Quality Management? Wisconsin Department of Transportation (WisDOT) construction projects require compliance with specifications. Different materials require different testing and at varying frequencies. In the past, WisDOT had the responsibility for checking materials compliance with the specifications. Thus, contractors did not always accept responsibility for controlling their own production process. Because of an expanding emphasis on quality, WisDOT has employed a system that relies on contractor Quality Control and Department Product Verification. Within this concept, the contractor is contractually required to perform a uniform and detailed process control called quality control (QC). WisDOT will also test a specified minimum number of samples taken for product quality verification (QV). Both QC and QV personnel will be required to be certified. Occasionally, WisDOT will conduct equipment and process inspections and comparative tests to validate the Quality Management Program. This latter operation is referred to as independent assurance testing. One of the main responsibilities of an HMA-TPC Technician is to know the contract requirements and specifications for each particular job. As an HMA-TPC Technician, you may be administering more than one contract at a time. BE FAMILIAR WITH THE SPECIFIC DETAILS OF EACH CONTRACT!!!

15 460.1 Description Section 460 Hot Mix Asphalt Pavement (1) This section describes HMA mixture design, providing and maintaining a quality management program for HMA mixtures, and constructing HMA pavement. Unless specifically indicated otherwise, references within 460 to HMA also apply to WMA Materials General Revise to regress air voids from 4.0% design to 3.0% target. This change was implemented in ASP 6 effective with the December 2016 letting. (1) Furnish a homogeneous mixture of coarse aggregate, fine aggregate, mineral filler if required, SMA stabilizer if required, recycled material if used, warm mix asphalt additive or process if used, and asphaltic material. Design mixtures conforming to table and table to 4.0% air voids to establish the aggregate structure. (2) Determine the target JMF asphalt binder content for production from the mix design data corresponding to 3.0% air voids (97% Gmm) target at the design the number of gyrations (Ndes). Add liquid asphalt to achieve the required air voids at Ndes. (3) For SMA, determine the target JMF asphalt binder content for production from the mix design data corresponding to 4.0% air voids (96% Gmm) target at Ndes Aggregates General (1) Provide coarse aggregates from a department-approved source as specified under Obtain the engineer's approval of the aggregates before producing HMA mixtures. (2) Furnish an aggregate blend consisting of hard durable particles containing no more than a combined total of one percent, by weight, of lumps of clay, loam, shale, soft particles, organic matter, adherent coatings, and other deleterious material. Ensure that the aggregate blend conforms to the percent fractured faces and flat & elongated requirements of table If the aggregate blend contains materials from different deposits or sources, ensure that material from each deposit or source has an LA wear percent loss meeting the requirements of table Freeze-Thaw Soundness (1) If the aggregate blend contains materials from different deposits or sources, ensure that material from each deposit or source has a freeze-thaw loss percentage meeting the requirements of table and Aggregate Gradation Master Range (1) Ensure that the aggregate blend, including recycled material and mineral filler, conforms to the gradation requirements in table The values listed are design limits; production values may exceed those limits. NOT FOR CONTRACT ADMINISTRATION Effective with the December 2017 Letting Standard Specifications

16 SIEVE TABLE AGGREGATE GRADATION MASTER RANGE AND VMA REQUIREMENTS No. 1 (37.5 mm) 50.0-mm 100 No. 2 (25.0 mm) 37.5-mm PERCENT PASSING DESIGNATED SIEVES No.3 (19.0 mm) 25.0-mm 90 max NOMINAL SIZE No. 4 (12.5 mm) No. 5 (9.5 mm) SMA No. 4 (12.5 mm) 19.0-mm 90 max SMA No. 5 (9.5 mm) 12.5-mm 90 max mm 90 max mm 90 max mm µm % MINIMUM VMA [1] 14.5 for LT and MT mixes. [2] 15.5 for LT and MT mixes Asphaltic Binders [1] 15.0 [2] (1) The department will designate the grade of asphaltic binder in the HMA Pavement bid item. Use the binder grade the bid item specifies. Do not change the PG binder grade without the engineer's written approval. The department will designate the grade of virgin asphaltic binder in the contract, however, the contractor may use virgin binder, modified binder, a blend of virgin and recovered binder, or a blend of modified and recovered binder. When the percent asphalt binder replaced exceeds the allowable limits in , provide test results from extracted and recovered binder to ensure that the resultant asphaltic binder conforms to the contract specifications Additives Hydrated Lime Antistripping Agent (1) If used in HMA mixtures, furnish hydrated lime conforming to ASTM C977 and containing no more than 8 percent unhydrated oxides. Percent added is by weight of the total dry aggregate Liquid Antistripping Agent (1) If used in HMA mixtures, add liquid antistripping agent to the asphaltic binder before introducing the binder into the mixture. Provide documentation indicating that addition of liquid antistripping agent will not alter the characteristics of the original asphaltic binder performance grade (PG) Stone Matrix Asphalt Stabilizer (1) Add an organic fiber, an inorganic fiber, a polymer-plastic, a polymer-elastomer, or approved alternate stabilizer to all SMA mixtures. If proposing an alternate, submit the proposed additive system, asphaltic binder, and stabilizer additive, along with samples of the other mixture materials to the department at least 14 days before the project let date. The department will approve or reject that proposed alternate additive system no later than 48 hours before the project let date. (2) Use a single additive system for all SMA pavement in the contract Warm Mix Asphalt Additive or Process (1) Use additives or processes from the department's APL. Follow supplier or manufacturer recommendations for additives and processes when producing WMA mixtures Recycled Asphaltic Materials (1) The contractor may use recycled asphaltic materials from FRAP, RAP, and RAS in HMA mixtures. Stockpile recycled materials separately from virgin materials and list each as individual JMF components. (2) Control recycled materials used in HMA by evaluating the percent binder replacement, the ratio of recovered binder to the total binder. Conform to the following: NOT FOR CONTRACT ADMINISTRATION Effective with the December 2017 Letting Standard Specifications

17 MAXIMUM ALLOWABLE PERCENT BINDER REPLACEMENT RECYCLED ASPHALTIC MATERIAL LOWER LAYERS UPPER LAYER RAS if used alone RAP and FRAP in any combination RAS, RAP, and FRAP in combination [1] [1] When used in combination the RAS component cannot exceed 5 percent of the total weight of the aggregate blend Recovered Asphaltic Binders (1) Establish the percent of recovered asphaltic binder from FRAP, RAP, and RAS for the mixture design according to AASHTO T164 using the appropriate dust correction procedure. If production test results indicate a change in the percent of recovered asphaltic binder, the contractor or the engineer may request a change in the design recovered asphaltic binder. Provide the department with at least 2 recent extraction samples supporting that change. Ensure that those samples were prepared according to CMM 8-65 by a WisDOT qualified laboratory. (2) The contractor may replace virgin binder with recovered binder up to the maximum percentage allowed under without changing the asphaltic binder grade. If using more than the maximum allowed under , furnish test results indicating that the resultant binder meets the grade the contract originally specified HMA Mixture Design (1) For each HMA mixture type used under the contract, develop and submit an asphaltic mixture design according to CMM 8-66 and conforming to the requirements of table and table The values listed are design limits; production values may exceed those limits. The department will review mixture designs and report the results of that review to the designer according to CMM NOT FOR CONTRACT ADMINISTRATION Effective with the December 2017 Letting Standard Specifications

18 TABLE MIXTURE REQUIREMENTS Mixture type LT MT HT SMA ESALs x 10 6 (20 yr design life) < <8 >8 LA Wear (AASHTO T96) 100 revolutions(max % loss) revolutions(max % loss) Soundness (AASHTO T104) (sodium sulfate, max % loss) Freeze/Thaw (AASHTO T103) (specified counties, max % loss) Fractured Faces (ASTM D5821) (one face/2 face, % by count) 65/ 75 / / /90 Flat & Elongated (ASTM D4791) (max %, by weight) 5 (5:1 ratio) 5 (5:1 ratio) 5 (5:1 ratio) 20 (3:1 ratio) Fine Aggregate Angularity (AASHTO T304, method A, min) Sand Equivalency (AASHTO T176, min) Gyratory Compaction Gyrations for Nini Gyrations for Ndes Gyrations for Nmax Air Voids, %Va (%Gmm Ndes) 4.0 (96.0) 4.0 (96.0) 4.0 (96.0) 4.0 (96.0) % Gmm Nini <= 91.5 [1] <= 89.0 [1] <= 89.0 % Gmm Nmax <= 98.0 <= 98.0 <= 98.0 Dust to Binder Ratio [2] (% passing 0.075/Pbe) Voids filled with Binder (VFB or VFA, %) [4] [5] [3] [5] [3] [5] Tensile Strength Ratio (TSR) (AASHTO T283) [6] no antistripping additive with antistripping additive Draindown (AASHTO T305) (%) 0.30 [1] The percent maximum density at initial compaction is only a guideline. [2] For a gradation that passes below the boundaries of the caution zone (ref. AASHTO M323), the dust to binder ratio limits are [3] For No. 5 (9.5mm) and No. 4 (12.5 mm) nominal maximum size mixtures, the specified VFB range is 70-76%. [4] For No. 2 (25.0mm) nominal maximum size mixes, the specified VFB lower limit is 67%. [5] For No. 1 (37.5mm) nominal maximum size mixes, the specified VFB lower limit is 67%. [6] WisDOT eliminates freeze-thaw conditioning cycles from the TSR test procedure Quality Management Program General (1) Provide and maintain a QC program defined as all activities, including mix design, process control inspection, sampling and testing, and process adjustments related to producing and placing HMA pavement conforming to the specifications. (2) The department will provide product quality verification as follows: 1. By conducting verification testing of independent samples. 2. By periodically observing contractor sampling and testing. 3. By monitoring required control charts exhibiting test results and control parameters. 4. By the engineer directing the contractor to take additional samples at any time during production. (3) Refer to CMM 8-36 for detailed guidance on sampling, testing, and documentation under the QMP. NOT FOR CONTRACT ADMINISTRATION Effective with the December 2017 Letting Standard Specifications

19 Contractor Testing Required Quality Control Program Personnel Requirements (1) Provide HTCP-certified sampling and testing personnel. Provide at least one full-time HMA technician certified at a level appropriate for sampling and production control testing at each plant site furnishing material to the project. Before mixture production begins, provide an organizational chart in the contractor's laboratory. Include the names, telephone numbers, and current certifications of personnel with QC responsibilities. Keep the chart updated. (2) Ensure that sampling and testing personnel are minimally qualified as follows [1] : - HMA technician certified at a level appropriate for sampling and production control testing. - HMA ACT [2]. [1] After informing the engineer, a non-certified person under the direct observation of a certified HMA technician may sample for a period not to exceed 3 calendar days. [2] A certified HMA technician must coordinate and take responsibility for the work an ACT performs. No more than one ACT can work under a single certified technician. (3) Have a certified HMA technician ensure that sampling and testing is performed correctly, analyze test results, and post resulting data. (4) Have an HMA technician certified at a level appropriate for process control and troubleshooting or mix design available to make necessary process adjustments Laboratory Requirements (1) Conduct QC testing in a facility conforming to the department's laboratory qualification program. (2) Ensure that testing equipment conforms to the equipment specifications applicable to the required testing methods Required Sampling and Testing Contracts with 5000 Tons of Mixture or Greater (1) Furnish and maintain a laboratory at the plant site fully equipped for performing contractor QC testing. Have the laboratory on-site and operational before beginning mixture production. (2) Obtain random samples and perform tests according to CMM Obtain HMA mixture samples from trucks at the plant. Perform tests the same day taking the sample. (3) Retain the split portion of the contractor HMA mixture and blended aggregate samples for 14 calendar days at the laboratory site in a dry, protected area. The engineer may decrease this 14-day retention period. At project completion the contractor may dispose of remaining samples if the engineer approves. (4) Use the test methods identified below, or other methods the engineer approves, to perform the following tests at a frequency greater than or equal to that indicated: Blended aggregate gradations: Drum plants: - Field extraction by CMM Belt samples, optional for virgin mixtures, obtained from stopped belt or from the belt discharge using an engineer-approved sampling device and performed according to AASHTO T11 and T27. Batch plants: - Field extraction by CMM Asphalt content (AC) in percent: AC by calculation. AC by nuclear gauge reading, optional. AC by inventory, optional. Bulk specific gravity of the compacted mixture according to AASHTO T166. Maximum specific gravity according to AASHTO T209. Air voids (Va) by calculation according to AASHTO T269. VMA by calculation according to AASHTO R35. (5) Test each design mixture at a frequency at or above the following: NOT FOR CONTRACT ADMINISTRATION Effective with the December 2017 Letting Standard Specifications

20 TOTAL DAILY PLANT PRODUCTION FOR DEPARTMENT CONTRACTS SAMPLES in tons PER DAY [1] 50 to to to to greater than 4200 see footnote [2] [1] Frequencies are for planned production. If production is other than planned, conform to CMM [2] Add a random sample for each additional 1500 tons or fraction of 1500 tons. Revise (6) to require field tensile strength ratio tests, without freeze-thaw conditioning, for each mixture. (6) Also conduct field tensile strength ratio tests according to AASHTO T283, without freeze-thaw conditioning cycles, on each mixture. Test each full 50,000 ton production increment, or fraction of an increment, after the first 5000 tons of production. Perform required increment testing in the first week of production of that increment. If field tensile strength ratio values are below the spec limit, notify the engineer. The engineer and contractor will jointly determine a corrective action Contracts with Less Than 5000 Tons of Mixture (1) Conform to modified as follows: - The contractor may conduct QC tests in an off-site laboratory. - No field tensile strength ratio testing is required Contracts with Less Than 500 Tons of Mixture (1) The engineer may waive QC testing on contracts with less than 500 tons of mixture. If testing is waived, acceptance will be by visual inspection unless defined otherwise by contract change order. (2) If HMA density testing is waived under , QC testing is also waived Temporary Pavements (1) The engineer may waive all testing for temporary pavements, defined for this purpose as pavements that will be placed and removed before contract completion Documentation Records (1) Document observations, inspection records, mixture adjustments, and test results daily. Note observations and inspection records in a permanent field record as they occur. Record process adjustments and JMF changes. Submit copies of the running average calculation sheets for blended aggregate, mixture properties, and asphalt content along with mixture adjustment records to the engineer each day. Submit testing records and control charts to the engineer in a neat and orderly manner within 10 days after paving is completed. (2) Continue charts, records, and testing frequencies, for a mixture produced at one plant site, from contract to contract Control Charts (1) Maintain standardized control charts at the laboratory. Record contractor test results on the charts the same day as testing. Record data on the standardized control charts as follows: - Blended aggregate gradation tests in percent passing. Of the following, plot those sieves the design specifications require: 37.5-mm, 25.0-mm, 19.0-mm, 12.5-mm, 9.5-mm, 2.36-mm, and 75-µm. - Asphalt material content in percent. - Air voids in percent. - VMA in percent. (2) Plot both the individual test point and the running average of the last 4 data points on each chart. Show QC data in black with the running average in red. Draw the warning limits with a dashed green line and the JMF limits with a dashed red line. The contractor may use computer generated black-andwhite printouts with a legend that clearly identifies the specified color coded components Control Limits Revise (1) to change tolerances on air voids in percent. This change was implemented in ASP 6 effective with the December 2016 letting. (1) Conform to the following control limits for the JMF and warning limits based on a running average of the last 4 data points: NOT FOR CONTRACT ADMINISTRATION Effective with the December 2017 Letting Standard Specifications

21 ITEM JMF LIMITS WARNING LIMITS Percent passing given sieve: 37.5-mm +/ / mm +/ / mm +/ / mm +/ / mm +/ / mm +/ / µm +/ /- 1.5 Asphaltic content in percent Air voids in percent [1] +1.3/ /-0.7 VMA in percent [2] [1] For SMA, JMF limits are +/-1.3 and warning limits are +/-1.0. [2] VMA limits based on minimum requirement for mix design nominal maximum aggregate size in table (2) Warning bands are defined as the area between the JMF limits and the warning limits Job Mix Formula Adjustment Revise (1) to the update reference to relocated CMM section. This change was implemented in ASP 6 effective with the December 2016 letting. (1) The contractor may request adjustment of the JMF according to CMM Have an HMA technician certified at a level appropriate for process control and troubleshooting or mix design submit a written JMF adjustment request. Ensure that the resulting JMF is within specified master gradation bands. The department will have a certified Hot Mix Asphalt, Mix Design, Report Submittals technician review the proposed adjustment and, if acceptable, issue a revised JMF. (2) The department will not allow adjustments that do the following: - Exceed specified JMF tolerance limits. - Reduce the JMF asphalt content unless the production VMA running average meets or exceeds the minimum VMA design requirement defined in table for the mixture produced. (3) Have a certified Hot Mix Asphalt, Troubleshooting, Process Control technician make related process adjustments. If mixture redesign is necessary, submit a new JMF, subject to the same specification requirements as the original JMF Corrective Action (1) When running average values trend toward the warning limits, consider taking corrective action. Document corrective actions undertaken. Include test results in the contract files and in running average calculations. (2) Notify the engineer if running average values exceed the warning limits. If two consecutive running average values exceed the warning limits, stop production and make adjustments. Do not restart production until after notifying the engineer of the adjustments made. Do not calculate a new running average until the fourth test after the required production stop. (3) If the process adjustment improves the property in question so that the running average after 4 additional tests is within the warning limits, the contractor may continue production with no reduction in payment. (4) If the adjustment does not improve the properties and the running average after 4 additional tests stays inside the warning bands, the mixture is nonconforming and subject to pay adjustment. (5) If the contractor fails to stop production and make adjustments when required, all mixture produced from the stop point to the point when the running average is back inside the warning limits is nonconforming and subject to pay adjustment. (6) If the running average values exceed the JMF limits, stop production and make adjustments. Do not restart production until after notifying the engineer of the adjustments made. Continue calculating the running average after the production stop. (7) If the air voids running average of 4 exceeds the JMF limits, the material is nonconforming. Remove and replace unacceptable material. The engineer will determine the quantity of material to replace based on the testing data using the methods in CMM 8-36 and an inspection of the completed pavement. If the engineer allows the mixture to remain in place, the department will pay for the mixture and asphaltic material as specified in NOT FOR CONTRACT ADMINISTRATION Effective with the December 2017 Letting Standard Specifications

22 (8) If the running average of 4 exceeds the JMF limits for other properties, and the engineer allows the mixture to remain in place, the department will pay for the mixture as specified in The engineer will determine the quantity of material subject to pay reduction based on the testing data and an inspection of the completed pavement (Vacant) Department Testing Quality Verification Program General (1) The engineer will conduct QV tests to determine the quality of the final product and measure characteristics that predict relative performance Personnel Requirements (1) The department will provide at least one HTCP-certified HMA technician, certified at a level appropriate for sampling and mixture production control testing, to observe QV sampling of project mixtures. (2) An HMA technician certified at a level appropriate for sampling and mixture production control testing, or an HMA ACT working under the HMA certified technician, will split samples and do the testing. An HMA technician certified at a level appropriate for sampling and mixture production control testing must coordinate and take responsibility for the work an ACT performs. No more than one ACT can work under a single certified technician. (3) An HMA technician certified at a level appropriate for sampling and mixture production control testing will ensure that sampling and testing is performed correctly, analyze test results, and post resulting data. (4) The department will make an organizational chart available at the testing laboratory and to the contractor before mixture production begins. The department's chart will include names, telephone numbers, and current certifications of QV testing personnel. The department will update the chart with appropriate changes, as they become effective Laboratory Requirements (1) The department will furnish and maintain a facility for QV testing conforming to the department's laboratory qualification program requirements and fully equipped to perform QV testing. In all cases, the department will conduct testing in a separate laboratory from the contractor's laboratory Department Verification Testing Requirements (1) HTCP-certified department personnel will obtain random samples by directly supervising HTCPcertified contractor personnel sampling from trucks at the plant. The department will sample according to CMM Sample size must be adequate to run the appropriate required tests in addition to one set of duplicate tests that may be required for dispute resolution. The engineer will split the sample for testing and retain the remaining portion for additional testing if needed. (2) The department will verify product quality using the test methods specified in (3), other engineer-approved methods, or other methods the industry and department HMA technical team recognizes. The department will identify test methods before construction starts and use only those methods during production of that material unless the engineer and contractor mutually agree otherwise. (3) The department will perform testing conforming to the following standards: Bulk specific gravity (Gmb) of the compacted mixture according to AASHTO T166. Maximum specific gravity (Gmm) according to AASHTO T209. Air voids (Va) by calculation according to AASHTO T269. VMA by calculation according to AASHTO R35. (4) The department will randomly test each design mixture at the following minimum frequency: FOR TONNAGES TOTALING: Less than 501 tons... no tests required From 501 to 5,000 tons... one test More than 5,000 tons... add one test for each additional 5,000-ton increment NOT FOR CONTRACT ADMINISTRATION Effective with the December 2017 Letting Standard Specifications

23 Documentation (1) The engineer will document observations during QV sampling, and review QC mixture adjustments and QC test results daily. The engineer will note results of observations and inspection records in a permanent field record as they occur Acceptable Verification Parameters Revise (1) to change acceptable verification parameters for Va. This change was implemented in ASP 6 effective with the December 2016 letting. (1) The engineer will provide test results to the contractor within 2 mixture-production days after obtaining the sample. The quality of the product is acceptably verified if it meets the following limits: - Va is within a range of 2.0 to 4.3 percent. For SMA, Va is within a range of 2.7 to 5.3 percent. - VMA is within minus 0.5 of the minimum requirement for the mix design nominal maximum aggregate size. (2) If QV test results are outside the specified limits, the engineer will investigate immediately through dispute resolution procedures. The engineer may stop production while the investigation is in progress if the potential for a pavement failure is present. (3) If production continues for that mixture design, the engineer will provide additional retained sample testing at the frequency provided for in CMM This supplemental testing will continue until the material meets allowable differences or as the engineer and contractor mutually agree Dispute Resolution (1) When QV test results do not meet the specified limits, the bureau's AASHTO accredited laboratory and certified personnel will referee test the retained portion of the QV sample and the retained portion of the nearest available previous QC sample. (2) The department will notify the contractor of the referee test results within 3 business days after receipt of the samples. (3) The department will determine mixture conformance and acceptability by analyzing referee test results, reviewing mixture project data, and inspecting the completed pavement all according to CMM Corrective Action (1) Remove and replace unacceptable material at no additional expense to the department. (2) The department will reduce pay for the tonnage of nonconforming mixture, as determined during QV dispute resolution, if the engineer allows that mixture to remain in place. If production of that mixture design continued during the investigation, the department will also adjust pay for that mixture forward to the next conforming QV or QC point. The department will pay for the affected mixture as specified in Independent Assurance Testing (1) The department will evaluate both the contractor and department testing personnel and equipment as specified in Construction General (1) Construct HMA pavement of the type the bid item indicates encoded as follows: Combined Bid Item Encoding NOT FOR CONTRACT ADMINISTRATION GRADATIONS (NMAS) TRAFFIC VOLUME BINDER DESIGNATION LEVEL mm LT Low S Standard mm MT Medium H Heavy mm HT High V Very Heavy mm E Extremely Heavy mm mm (2) Construct HMA pavement conforming to the general provisions of Effective with the December 2017 Letting Standard Specifications

24 Thickness (1) Provide the plan thickness for lower and upper layers limited as follows: NOMINAL MINIMUM LAYER MAXIMUM LOWER MAXIMUM UPPER MAXIMUM SINGLE SIZE THICKNESS LAYER THICKNESS LAYER THICKNESS LAYER THICKNESS [3] in inches in inches in inches in inches No. 1 (37.5 mm) No. 2 (25.0 mm) No. 3 (19.0 mm No. 4 (12.5 mm) [1] [4] [2] No. 5 (9.5 mm) [1] [4] [2] 2 3 [1] SMA mixtures use nominal size No. 4 (12.5 mm) or No. 5 (9.5 mm). [2] SMA mixtures with nominal sizes of No. 4 (12.5 mm) and No. 5 (9.5 mm) have no maximum lower layer thickness specified. [3] For use on cross-overs and shoulders. [4] Can be used for a leveling layer or scratch coat at a reduced thickness HMA Pavement Density Maximum Density Method Minimum Required Density Revise (1) table to increase field density requirements. This change was implemented in ASP 6 effective with the December 2016 letting. (1) Compact all layers of HMA mixture to the density table shows for the applicable mixture, location, and layer. LOCATION TRAFFIC LANES [2] SIDE ROADS, CROSSOVERS, TURN LANES, & RAMPS SHOULDERS & APPURTENANCES TABLE MINIMUM REQUIRED DENSITY [1] PERCENT OF TARGET MAXIMUM DENSITY LAYER MIXTURE TYPE LT and MT HT SMA [5] LOWER 93.0 [3] 93.0 [4] UPPER LOWER ] 93.0 [4] UPPER LOWER UPPER [1] The table values are for average lot density. If any individual density test result falls more than 3.0 percent below the minimum required target maximum density, the engineer may investigate the acceptability of that material. [2] Includes parking lanes, bike lanes, and park-and-ride lots as defined by the contract plans. [3] Minimum reduced by 2.0 percent for a lower layer constructed directly on crushed aggregate or recycled base courses. [4] Minimum reduced by 1.0 percent for a lower layer constructed directly on crushed aggregate or recycled base courses. [5] The minimum required densities for SMA mixtures are determined according to CMM Pavement Density Determination (1) The engineer will determine the target maximum density using department procedures described in CMM The engineer will determine density as soon as practicable after compaction and before placement of subsequent layers or before opening to traffic. (2) Do not re-roll compacted mixtures with deficient density test results. Do not operate continuously below the specified minimum density. Stop production, identify the source of the problem, and make corrections to produce work meeting the specification requirements. (3) A lot is defined in CMM 8-15 and placed within a single layer for each location and target maximum density category indicated in table The lot density is the average of all samples taken for that NOT FOR CONTRACT ADMINISTRATION Effective with the December 2017 Letting Standard Specifications

25 lot. The department determines the number of tests per lot according to either the linear sublot system or the nominal tonnage system defined in CMM (4) A certified nuclear density technician, or a nuclear density ACT working under a certified nuclear density technician, will locate samples and perform the testing. A certified nuclear density technician must coordinate and take responsibility for the work an ACT performs. No more than one ACT can work under a single certified technician. The responsible certified technician will ensure that sample location and testing is performed correctly, analyze test results, and provide density results to the contractor weekly Waiving Density Testing (1) The engineer may waive density testing for one or more of the following reasons: 1. It is impracticable to determine density by the lot system. 2. The contract contains less than 750 tons of a given mixture type placed within the same layer and target maximum density category. (2) If the department waives density testing notify the contractor before paving. The department will accept the mixture by the ordinary compaction procedure as specified in (3) If HMA QC testing is waived under , density testing is also waived Measurement (1) The department will measure the HMA Pavement bid items acceptably completed by the ton as specified in Payment General (1) The department will pay for measured quantities at the contract unit price under the following bid items: ITEM NUMBER DESCRIPTION UNIT HMA Pavement (gradation) LT (binder)(designation) TON HMA Pavement (gradation) MT (binder)(designation) TON HMA Pavement (gradation) HT (binder)(designation) TON HMA Pavement (gradation) SMA (binder)(designation) TON Incentive Density HMA Pavement DOL HMA Pavement General (1) The department will pay for the HMA Pavement bid items at the contract unit price subject to one or more of the following adjustments: 1. Disincentive for density of HMA pavement as specified in Incentive for density of HMA pavement as specified in Reduced payment for nonconforming smoothness as specified in Reduced payment for nonconforming QMP HMA mixtures as specified in (2) Payment for the HMA Pavement bid items is full compensation for providing HMA pavement including binder; for mixture design; for preparing the foundation; and for QMP and aggregate source testing. (3) If provided for in the plan quantities, the department will pay for a leveling layer, placed to correct irregularities in an existing paved surface before overlaying, under the pertinent paving bid item. Absent a plan quantity, the department will pay for a leveling layer as extra work. (4) The department will administer pay reduction for nonconforming QMP mixture under the Nonconforming QMP HMA Mixture administrative item. The department will reduce pay based on the contract unit price for the HMA Pavement bid item. (5) The department will reduce pay for nonconforming QMP HMA mixtures as specified in , starting from the stop point to the point when the running average of 4 is back inside the warning limits. The engineer will determine the quantity of material subject to pay reduction based on the testing data and an inspection of the completed pavement. The department will reduce pay as follows: NOT FOR CONTRACT ADMINISTRATION Effective with the December 2017 Letting Standard Specifications

26 PAYMENT FOR MIXTURE [1] [2] PRODUCED WITHIN PRODUCED OUTSIDE ITEM WARNING BANDS JMF LIMITS Gradation 90% 75% Asphalt Content 85% 75% Air Voids 70% 50% VMA 90% 75% [1] For projects or plants where the total production of each mixture design requires less than 4 tests refer to CMM [2] Payment is in percent of the contract unit price for the HMA Pavement bid item. The department will reduce pay based on the nonconforming property with lowest percent pay. [3] In addition to any pay adjustment listed in the table above, the department will adjust pay for nonconforming binder under the Nonconforming QMP Asphaltic Material administrative item. The department will deduct 25 percent of the contract unit price of the HMA Pavement bid item per ton of pavement placed with nonconforming PG binder the engineer allows to remain in place. Revise (6) to define mixture subject to a 50 percent pay reduction. This change was implemented in ASP 6 effective with the December 2016 letting. (6) If during a QV dispute resolution investigation the department discovers mixture with 1.5 > Va > 5.0 or VMA more than 1.0 below the minimum allowed in table 460-1, and the engineer allows that mixture to remain in place, the department will pay for the quantity of affected material at 50 percent of the contract price. (7) If the department waives density testing under , the department will not adjust pay under either or (8) Restore the surface after cutting density samples as specified in (1) at no additional cost to the department Disincentive for HMA Pavement Density (1) The department will administer density disincentives under the Disincentive Density HMA Pavement administrative item. If the lot density is less than the specified minimum in table 460-3, the department will reduce pay based on the contract unit price for the HMA Pavement bid item for that lot as follows: DISINCENTIVE PAY REDUCTION FOR HMA PAVEMENT DENSITY PERCENT LOT DENSITY PAYMENT FACTOR BELOW SPECIFIED MINIMUM (percent of contract price) From 0.5 to 1.0 inclusive 98 From 1.1 to 1.5 inclusive 95 From 1.6 to 2.0 inclusive 91 From 2.1 to 2.5 inclusive 85 From 2.6 to 3.0 inclusive 70 More than 3.0 [1] [1] Remove and replace the lot with a mixture at the specified density. When acceptably replaced, the department will pay for the replaced work at the contract unit price. Alternatively the engineer may allow the nonconforming material to remain in place with a 50 percent payment factor. (2) The department will not assess density disincentives for pavement placed in cold weather because of a department-caused delay as specified in (3) Incentive for HMA Pavement Density Revise (1) to the change air void requirements to qualify for density incentive. (1) If the lot density is greater than the minimum specified in table and all individual air voids test results for that mixture placed during the same day are within percent, the department will adjust pay for that lot as follows: NOT FOR CONTRACT ADMINISTRATION INCENTIVE PAY ADJUSTMENT FOR HMA PAVEMENT DENSITY PERCENT LOT DENSITY ABOVE SPECIFIED MINIMUM PAY ADJUSTMENT PER TON [1] From -0.4 to 1.0 inclusive $0 From 1.1 to 1.8 inclusive $0.40 More than 1.8 $0.80 [1] The department will prorate the pay adjustment for a partial lot. Effective with the December 2017 Letting Standard Specifications

27 (2) The department will adjust pay under the Incentive Density HMA Pavement bid item. Adjustment under this item is not limited, either up or down, to the bid amount the schedule of items shows. (3) For shoulders paved integrally with the traffic lane, if the traffic lane does not meet incentive requirements, the department will not pay incentive on the integrally paved shoulder. NOT FOR CONTRACT ADMINISTRATION Effective with the December 2017 Letting Standard Specifications

28 Construction and Materials Manual Chapter 8 Materials Testing, Sampling, Acceptance Section 36 QMP - HMA Wisconsin Department of Transportation Materials sampling and testing methods and documentation procedures prescribed in chapter 8 of the CMM are mobilized into the contract by standard spec and standard spec Hot Mix Asphalt (HMA) Quality Management Program sampling, testing, materials properties, and documentation as prescribed in CMM 8-36 are called into the contract by standard spec General This section addresses the standard specification for Quality Management Program (QMP), Asphaltic Mixture. The QMP for Hot Mix Asphalt (HMA) is detailed in standard spec The following information is provided as additional reference, interpretation, and guidance for procedures outlined in those specifications. Overview - WisDOT QMP Requirements: - Personnel and required certifications CMM and standard spec ) - Laboratory facilities (CMM and standard spec ) - Random sampling and sampling frequency (CMM and standard spec ) - Required testing (and calculated properties) (CMM and standard spec ) - Mixture bulk specific gravity (Gmb) - Mixture maximum specific gravity (Gmm) - Air voids (Va) - VMA (voids in mineral aggregate) - Aggregate gradation - Percent binder content - Documentation (CMM and standard spec ) - Records - Control charts - Control limits (standard spec ) - Warning bands - Job mix formula adjustments (CMM and standard spec ) - Corrective action (standard spec ) - Verification program (CMM and standard spec ) The following sections identify and further attempt to clarify procedures used during field production of HMA under the QMP Definitions Rule of Retained: Split samples for comparison testing are retained. In order to test a retained portion of any sample, communications must occur between the department and contractor QMP teams. The department has ownership of QMP required split samples. There is implied joint ownership between contractor and department on any additional QC samples recorded. NOT FOR CONTRACT ADMINISTRATION Mixture production days: Days of production of a specific design mixture being tested under QMP. No more than two working days is intended for getting test results. Working days: Calendar day, except Saturdays, Sundays, and department-specified holidays. Nonconforming materials: Mixture not meeting acceptable verification parameters, but allowed to be left in place with appropriate payment reduction. Unacceptable materials: Mixture not meeting acceptable verification parameters and being required to be removed and replaced. Teams: Personnel listed on QMP organizational charts. May 2017 Page 1

29 CMM 8-36 QMP - HMA Personnel Requirements (Through HTCP) The following list summarizes minimum personnel requirements and associated certifications to satisfy QMP Asphalt activities. 1. QC: Production process - Sampling and testing: HMATech at a level recognized for mixture production testing (formerly known as HMATech 1). - Production process changes: HMATech at a level recognized for production process control and troubleshooting (formerly known as HMATech 2). - Mix design: at a level recognized for doing mix design work (formerly known as HMATech 3). 2. QV: Department quality verification - Sampling and testing: at a level recognized for mixture production testing (formerly known as HMATech 1). - Production process change review: at a level recognized for doing mix design work (formerly known as HMATech 3) Laboratory Requirements The laboratory must be: - Furnished with equipment to comply with daily testing and communication requirements (calibrated testing equipment, phones, faxes, copy machines, etc.). - Located at the plant site and operational before production. - A Wisconsin Laboratory Qualification Program participant. Any laboratory producing air void test data to comply with QMP requirements must have a Superpave Gyratory Compactor (SGC). The intent is for the Gmm and Gmb materials to be tested at the same facility Sampling Hot Mix Asphalt At the beginning of each day the contractor determines the anticipated tonnage to be produced. The frequency of sampling (minimum number of required tests for the day s anticipated production) is defined by the latest (QMP) HMA mixture standard spec A test sample is obtained randomly from each sublot. Example 1 The approximate location of each sample within the prescribed sublots is determined by selecting random numbers using ASTM D3665 or by using a calculator or computerized spreadsheet that has a random number generator. The random numbers selected are used in determining when a sample is to be taken and will be multiplied by the sublot tonnage. This number will then be added to the final tonnage of the previous sublot to yield the approximate cumulative tonnage of when each sample is to be taken. To allow for plant start-up variability, the procedure calls for the first random sample to be taken at 50 tons or greater per production day (not intended to be taken in the first two truckloads). Random samples calculated for 0-50 ton should be taken in the next truck (51-75 ton). NOT FOR CONTRACT ADMINISTRATION May 2017 Page 2

30 CMM 8-36 QMP - HMA Example 2 Required Sample Sublot Sample Tonnage Range Random No. ASTM D3665 Sublot Sample Ton (Random No. x Sublot ton) End of Previous. Range Cumulative Sample Tonnage RN x 600= RN x 900= RN x 1200= This procedure is to be used for any number of samples per day. If the anticipated day s production is 1900 tons, then the third random sample would be calculated between 1501 and 1900 tons (i.e., x 400 = 262 and = 1762) rather than the calculated 2287 tonnage. If production doesn t meet the anticipated tonnage to allow for obtaining the next randomly generated sample, then an additional sample will be taken within the last 100 tons of the day to fulfill the sampling frequency requirement defined in standard spec (5) (Document reasons for any non-compliance Note: If this scenario occurs, by definition, this sample qualifies as being a random sample within the QMP program frequency requirements, meaning, if anticipated tonnage is exceeded, a second sample should not be taken within the same interval. It s intended that the plant operator not be advised ahead of time when samples are to be taken. If the plant operator is involved in recording a Pb (%AC) to match up with the mix sample tonnage, then notification need not be earlier than 60 minutes before the mix sample being taken. If belt samples are used during troubleshooting, the blended aggregate will be obtained when the mixture production tonnage approximates the sample tonnage. For plants with storage silos, this could be up to 60 minutes in advance of the mixture sample that s taken when the required tonnage is shipped from the plant. QC Sample: - Sample size only requires one test portion and one retained portion. QV Sample: - Must be directly observed by the project engineer. - Project engineer takes immediate possession. - The initial split of QV and QV-retained, can be performed by using a quartermaster. If the contractor performs this split, the project engineer, before taking possession, must directly observe it Sampling from the Truck Box Sampling will be the contractor's responsibility. Truck box sampling presents some safety hazards because it is necessary to climb atop the truck box and stand on the hot mixture while sampling. Special care should be exercised by the contractor or his designated representative as the sample is procured to prevent falls or burns. A shovel or mechanical sampling device approved by the department should be of such size and configuration that the sample can be obtained without spilling or roll off. Note: To satisfy this requirement with a flat bottom shovel, it is necessary to attach 2- to 4-inch vertical sides to the shovel. NOT FOR CONTRACT ADMINISTRATION May 2017 Page 3

31 CMM 8-36 QMP - HMA Sample Location in Truck Figure 1 Truck Box Sampling When the last batch has been dumped into the truck box, the sampler must establish a reference point on the surface of the load, either at the high point, if a conical shape exists, or near the middle of the truck box if the surface shows no such conical shape. Then at least three incremental sample points (unless approved mechanical sampling device is capable of obtaining a representative minimum sample size in less than 3 locations) should be established about midway between the previously established point and the sides of the truck and equally spaced around the load as seen above in Figure 1. The sampling shovel or other approved device can be inserted into the upper two to three inches of mixture to extract the sample increments QC Sample Sizes: - Minimum sample sizes are referenced below and are guidance for meeting requirements for test completion. Mixture NMAS Sample Size < 12.5mm (1/2"), Gradation #4 70 lb 19.0mm mm (3/4" 1"), Gradations # lb > 37.5mm ( 1-1/2"), Gradation # lb - The total sample for larger NMAS (nominal maximum aggregate size) mixtures will be enough to provide the required minimum testing sample size as defined in Figure 3. - The retained split must be half of the QC sample QV Sample Sizes: Use same guidance as QC sample size (trouble shooting may involve need for a gradation) Sample Identification The contractor is responsible for obtaining and splitting samples. When a mixture sample is procured, it must be quartered, and the QV and retained portions placed in a boxes (dimensions of approximately 10 x 8 x 8 such as Uline S-19062), and labeled as directed below. Figure 2 provides an example label. The label must include the following items: 1. Contractor Testing Lab and Certified Technician Name 2. QC, QC-ret, QV, QV-ret 3. State project ID 4. Date 5. Sample number 6. Type of asphaltic mixture 7. State mix design ID (250-XXXX-YR) 8. Percent binder 9. Daily tonnage sampled NOT FOR CONTRACT ADMINISTRATION May 2017 Page 4

32 CMM 8-36 QMP - HMA 10. Current Gsb Figure 2 Example of Sample Labeling NOTE: The cumulative/total tons representing mix design production are to be recorded on the QC data sheets Reduction of HMA Samples to Testing Size For QC sample reduction the HMA sample in the containers is mixed and quartered. The quartering process should then proceed as follows: Step 1: 1. Quarter the sample into Test and Retained samples. Place entire sample on table, quickly re-mix and quarter to minimize temperature loss. Quarter the Test & Retained samples as shown on Figure 3. For 1/2" mixes start with at least a total of 70 lbs of HMA. Figure 3 Superpave Sample, 70 lbs NOT FOR CONTRACT ADMINISTRATION 2. Diagonal quarters, as indicated on the sketch, must be combined to form the retained sample (A + C) and the test sample (B + D). The retained sample must be bagged, labeled, and stored in a safe dry place. The retained samples may be tested using the rule of retained (see Definitions section). 3. The test sample (B + D) is then further quartered for the specified tests. Continue the quartering process in Step 2 for the test materials until individual samples are in the oven Step 2: The 35 lbs of HMA material for testing from Step 1 is to be further reduced for testing according to the following sketch (see Figure 4). May 2017 Page 5

33 CMM 8-36 QMP - HMA Figure 4 Superpave Sample, (35 lbs) Figure 5 Minimum Testing Sample Sizes For QV samples a Solvent Extraction Gradation (CMM ) isn t routinely required Use of Alternative Sampling / Quartering Devices (ex: Quartermaster) Use of other devices to assist in the sampling and quartering procedures may be used with approval of the department. The Quartermaster is one such device. A picture of a Quartermaster device is shown in Figure 6. Figure 6 Quartermaster Quartering Device NOT FOR CONTRACT ADMINISTRATION May 2017 Page 6

34 CMM 8-36 QMP - HMA Example 3 SMA Sampling and Testing Guidance added Reduction of SMA Test Strip Samples to Testing Size The SMA Test Strip volumetric samples require a 3-part split. For QC or QV sample reduction, the SMA sample is passed through a Quartermaster. In a 3-part split, the individual samples are labelled/referred to in accordance with the team expected to test that particular split. In other words, this process must yield a QC, QV, and retained sample (for BTS, if needed). After splitting, further handle each test portion in accordance with Reduction of SMA during Main Production After completion of the test strip, a 3-part sample is no longer used and sampling/splitting returns to conventional splits, yielding portions for testing and retained portions (i.e., QC sample yields a QC for testing and a QC-retained, while a QV sample must yield a QV sample for testing plus a QV-retained, at a minimum) Further Reduction of SMA Samples to Test Sizes The approximately 65 lbs of SMA material is to be further reduced for testing according to Figure 7. Figure 7 SMA Sample (Laboratory Split of approx. 65 lbs) NOT FOR CONTRACT ADMINISTRATION As can be seen here, each test portion should yield the following: - Four Gmb specimens - Two Gmm specimens - One Extraction/Gradation specimen May 2017 Page 7

35 CMM 8-36 QMP - HMA Required Testing and Calculated Properties Note: If the number you are rounding is followed by 5, 6, 7, 8, or 9, round up. If the number you are rounding is followed by 0, 1, 2, 3, or 4, round down. Example: becomes 14.2 and becomes QC Tests QC testing must be completed, and data posted, on the day the sample was taken or as approved by the project engineer. For administration of projects requiring only one, two, or three single tests per mix design, apply the following tolerances table for mixture evaluation: - Va = % ( % for SMA) - VMA = from required minimums for Table AC = within -0.3 of JMF For results not meeting the above ranges, apply pay in accordance with the Produced Outside JMF Limits guidance listed in standard spec (6) QV Tests The following tests are to be performed in determining product Quality Verification: -Bulk specific gravity of the mixture (Gmb per AASHTO T 166) -Maximum specific gravity of the mixture (Gmm per AASHTO T 209) -Air voids (Va per AASHTO T 269, calculation) -Voids in the mineral aggregate (per AASHTO R 35, using current field Gsb) WisDOT Test Method for Solvent Extraction Gradation (Bucket Method) Scope 1. This is a quick method to determine the gradation of the aggregate from an asphaltic mixture when the asphalt content of the mixture is known Apparatus 1. Pans (approximately 12 by 8 by 3 deep), bowls (approximately 10 quarts) or pails (approximately 10 quarts). 2. Balance must be an electronic type with a 5-20 kg capacity and sensitivity to 0.1g. 3. Solvent must be a biodegradable, high flash and nontoxic asphalt extractant Procedure 1. Obtain a representative sample of the mixture. Note that the mixture sample size needs to be larger than the specified minimums required for the mixture aggregate size when determining the gradation (this is in order to account for the weight of the binder being washed out). Dry the sample for 10 to 20 minutes in an oven at 275 F ± 20 F (124C 146C), weigh and record to the nearest 0.1 gram. RAP stockpile samples must be heated until dry, approximately 30 to 60 minutes. 2. Determine the percent asphalt being added to the mixture at the time the sample was obtained (could be from the settings of the asphalt plant for plant produced mixtures) and record. For RAP stockpile samples, use the asphalt content shown for the RAP on the mixture design. NOT FOR CONTRACT ADMINISTRATION 3. Place warm mixture in a pan, pail or bowl and cover with solvent (due to the flammability potential of the solvents, it s not recommended to heat the solvent prior to adding to the mixture sample). Gently agitate the sample, frequently, with a spoon or spatula. Keeping the sample warm during the soaking process will aid in extracting the binder from the aggregate. Continue to soak and agitate the sample for 15 to 30 minutes (30 to 60 minutes for RAP mixtures or RAP stockpiles samples). May 2017 Page 8

36 CMM 8-36 QMP - HMA Note: Excessive soaking time in the solvent will require more water washes and will cause more smoking during the drying operation. 4. Decant the solvent, pouring over a No. 8 sieve nested over a No. 200 sieve. Dispose of the used solvent by an approved method. Add water, agitate and decant over the same sieves. Continue washing with water until the wash water is clear (straw). Material retained on either of the sieves is washed back into the sample. Decant off any excess water. Care should be taken to avoid the loss of particles. Note:It has been the Wisconsin experience that, on average, two full-strength solvent washes, before proceeding with the final water wash will aid in extracting the binder from the aggregate when using RAP mixtures. 5. Dry the sample to a constant weight in an oven or on a hot plate. Stir the cleaned aggregate sample during the drying process to free trapped moisture. Avoid excessive temperature in the drying process. 6. Conduct a sieve analysis on the extracted aggregate (AASHTO Test Method T 27) in order to identify the gradation of the sample Calculation 1. Calculate the total dry weight of the aggregate as follows: Wagg = Wmix * (1-(AC%/100)) Where: Wagg = Total dry weight of the aggregate Wmix = Total dry weight of the mixture sample obtained during Step 1 of CMM AC% = Percent asphalt determined in Step 2 of CMM Calculate the gradation as required using the dry weight of aggregate (Wagg) as determined above Report 1 The results of the sieve analysis should be reported to the nearest 0.1 percent. 2 Field experience has demonstrated that high flash solvent performs better when applied to an asphaltic mixture sample that is warm. Always follow the specified pre-soaking and rinse conditions. Document anytime in which high flash solvent is soaked other than the prescribed pre-soaking duration. Always comply with the specified test and safety procedures Asphalt Content by Ignition Oven (%AC) WisDOT Modified AASHTO T 308 Ignition Oven Testing Guidance added. NOTE: ASPHALT CONTENT BY IGNITION OVEN IS ONLY APPLICABLE TO WISDOT PWL JOBS FOR 2017 All information collected in accordance with the details below is for evaluation purposes only and is not to be used for pay adjustment calculations at this time. In addition to ignition oven requirements, mix designers must submit the following to BTS at the time of mix design submittal for 2017 WisDOT PWL projects: 1. Seven 4800 gram samples of batched virgin aggregate 2. Eight batched samples of RAP and accompanying documentation of stockpile %AC 3. Eight batched samples of RAS and accompanying documentation of stockpile %AC NOT FOR CONTRACT ADMINISTRATION May 2017 Page 9

37 CMM 8-36 QMP - HMA 4. Four individual quarts or one gallon of asphalt binder used in mix design During production, provide to the Department, results of Ignition Oven burns conducted in accordance with the following: Follow AASHTO T 308 Determining the Asphalt Binder Content of Hot Mix Asphalt (HMA) by Ignition Method, Method A, with the following modification: 1.1 This test method covers the determination of asphalt binder content of hot mix asphalt (HMA) by ignition oven at temperatures that reach the flashpoint of the binder in a furnace. The means of specimen heating may be the convection method. The aggregate remaining after burning can be used for sieve analysis using T The asphalt binder in the HMA is ignited using the furnace equipment applicable to the particular method. This procedure covers two methods. Method A requires an ignition furnace with an internal balance. 5.1 Ignition Furnace A forced-air ignition furnace that heats the specimens be convection method. The convectiontype furnace must be capable of maintaining a temperature of o C ( o F). The furnace chamber dimensions shall be adequate to accommodate a specimen size of 3500 g. The furnace door shall be equipped so that the door cannot be opened during the ignition test. A method for reducing furnace emissions shall be provided. The furnace shall be vented into a hood or to the outside and, when set up properly, shall have no noticeable odors escaping into the laboratory. The furnace shall have a fan capable of pulling air through the furnace to expedite the test and reduce the escape of smoke into the laboratory For the convection-type furnace, preheat the ignition furnace to o C ( o F) or to the temperature determined by the correction factor process in the Annex. Manually record the furnace temperature (set point) prior to the initiation of the test if the furnace does not record automatically Delete this step Delete Note 6 Delete Section Test Method A; 11.1 Precision Criteria for judging the acceptability of ignition burn results for asphalt content obtained by Method A is given in Table 2. A2.4 Prepare two correction specimens at the JMF design asphalt content and gradation. Aggregate used for the correction specimens shall be sampled from the material designated for use in production A2.6 Test the specimens in accordance with Method A or Method B of the procedure. A2.8.1 If the asphalt binder correction factor exceeds 1.0 percent, the test temperature should be lowered to o C ( o F) for a convection-type furnace. If there is no improvement in the correction factor, it is permissible to use the higher temperature. Note A2 The temperature for determining the asphalt binder content of HMA specimens by this procedure shall be the same temperature determined for the correction specimens. Delete A2.8.2 through A2.9.2 Add CMM for WisDOT calibration via BTS extraction Ignition Oven Correction Factor The Department s Bureau of Technical Services AASHTO accredited laboratory will provide an asphalt content measurement to the contractor, to be used in calculating ignition oven correction factor per oven, per mix design used on a State project. This asphalt content will be measured using material obtained at the plant on the first day of production, in accordance with the following: 1. The Contractor will obtain a representative sample of mixture, witnessed by a State representative, from the truck box on the first day of plant production. The sample size must be at least 150 lbs. The Contractor will split the sample using a quartermaster and supply a minimum of 2-35 lb. samples to the QV representative. NOT FOR CONTRACT ADMINISTRATION 2. The QV representative takes possession of the split sample and delivers the WisDOT split sample to the WisDOT Regional Laboratory within 12 hours of sampling. 3. The WisDOT Regional lab will send one of the initial split sample boxes (35 lbs.) to the WisDOT Central Laboratory (BTS) within one (1) working day of receiving the sample. WisDOT Central Lab will perform a Chemical extraction to determine an extracted asphalt binder content of the mixture. Results will be completed and reported by the end of the second working day after arrival at the Central Lab. 4. The contractor has the option to run a chemical extraction following AASHTO T 164, otherwise the result obtained by BTS will be used to determine the correction factor for all ovens, i.e., Region, Contractor, and BTS for that mix. 5. When the Contractor wishes to compare their extracted asphalt content results to that obtained by BTS, the following apply: May 2017 Page 10

38 CMM 8-36 QMP - HMA A. If results from both parties are within 0.40 %AC of each other, the BTS result is considered validated and will be used. B. If the two results are not within 0.40 %AC of each other, a retest of the material will be conducted by WisDOT (BTS) from the same split sample. If the retest is within 0.20 %AC of the first sample run by the department, the average of the two WisDOT test results will be used. C. If the retest does not meet the tolerance of 0.20 %AC, a third split of the same sample will be tested by WisDOT (BTS) and compared to the first two sample results. If the result is within 0.20 %AC of one of the first two tests, the average value of those two closest test results will be used. 6. WisDOT- Regional Lab and the contractor will each test two ignition calibration samples from the same split sample (step 1). WisDOT modified AASHTO T 308 will be conducted in accordance with CMM Once the WisDOT- Regional Lab and contractor have completed their ignition oven tests, each will average the values obtained from their respective two tests and calculate the difference between that average value and the asphalt content provided by WisDOT (BTS) determined from step 3 or 5, as applicable. 8. Each ignition oven shall have proper documentation indicating the following: contractor mix identification, date of calibration, WisDOT 250# and correction factor. 9. The calibration procedure for a given mix must be verified (re-calculated) if any of the following occur: - Exceed 50,000 tons of mixture produced - An individual aggregate (virgin or RAP) changes by more than 5 percent from the JMF, - Any change in the percentage of RAS HMA Compaction - AASHTO T Preheat specimen molds (charging funnels, spatulas, etc.) to 300F. 2. Heat sample, in an open container, to a compaction temperature of 275F + 5F in an oven between 285F 320F for no more than 1 hour. If binder modifiers or additives are used, compact to the supplier s temperature recommendations.. Note, for such mixes, e.g. WMA, this compaction temperature should match that specified on the mix design submittal. After quartering to test size, if the mix sample is within the proper compaction temperature range, then the specimen can be compacted without further heating. 3. Place specimen protection disc into the bottom of the mold and charge the mold with the mix sample. The sample size should be enough to attain a final specimen height of 115mm + 5mm and is unique to the mix design. For Wisconsin aggregates and designs a range of g is generally appropriate. Charging the mold should be accomplished in one lift action or motion so as to avoid segregating the sample inside the mold. Additional funnels or scoop chutes may be used in order to accomplish this. 4. Lightly level off the top of the sample and place a specimen protection disc on top. 5. Load the mold into the SGC and compact to the appropriate Ndes for the mixture type being produced by applying 600kPa 18kPa, at an internal angle of After compaction is completed the specimen is extruded, protection papers are removed, the briq is labeled, and cooling by fan is required for a period of at least 1 hour. If the mixture is extremely fine or tender, then the initial 5-10 minutes of cooling should take place while the specimen is only partially extruded to aid in handling. 7. Height measurements should be recorded and retained with each specimen. 8. Reheat the mold to the compaction temperature if reusing for the second specimen. All SGCs being used for QMP specimen preparation will conform to the requirements for calibration as listed in the departments Laboratory Qualification Program. Recalibration may be necessary if the testing variation between labs exceeds allowable differences or when a continued bias exists in the data attributed to the preparation of the specimen Bulk Specific Gravity (Gmb) AASHTO T 166 Determine bulk specific gravity, Gmb, using AASHTO T166. NOT FOR CONTRACT ADMINISTRATION - Weigh the specimens in air and record (designated this weight as A). - Immerse the specimens in 77 2F water bath for 3 to 5 minutes. - Weigh in water, and record (designating this weight as C). - Surface dry the specimens by blotting quickly with a damp towel and then weigh in air (include any water that may drain from voids in specimens), and record (designating this weight as B). - Calculate the Gmb to three decimal places (0.001). May 2017 Page 11

39 CMM 8-36 QMP - HMA Determine the average bulk specific gravity for both specimens. If one of the individual specimens deviates by more than ±0.015 from the average, results are considered suspect and a new set of specimens is to be compacted from the contractor retained sample (following the rule-of-retained). Determine bulk specific gravity, Gmb for SMA by using (Corelok System or equivalent vacuum system) in accordance with AASHTO T 331. Additional information on using the Corelok for Gmb is provided in the following link: CoreLok -Bulk Specific Gravity Video For the QC or QV testing, determine the average bulk specific gravity, Gmb, for SMA material by averaging 4 specimens. If one of the individual specimens deviates by more than +/ from the average, results are considered suspect and the result furthest from the average should be removed from the calculation. Calculate the average using the remaining 3 specimens. After compaction, place mold in front of a fan for approximately 15 minutes before extruding Maximum Specific Gravity of the Mixture (Gmm) - AASHTO T 209 Determine maximum specific gravity, Gmm, using AASHTO T Use the appropriate sample size Figure 5. - Subject the Gmm sample to the same heating condition and time period as the Gmb material. - Begin to cool the sample. While sample is cooling, break up sample to pieces no greater than ¼, and continue to cool to an ambient room temperature. - Place material into a calibrated container and determine the actual dry weight of the sample. - Add 77F water to cover the sample. - Apply required vacuum for minutes, agitating material every 2 minutes minimum. - After the vacuum time period, completely fill the container with 77F water and determine the volume of the sample. - Bowl Method: by suspending the container underwater and weighing - Flask Method: by weighing the container filled with water and sample (in air). - Correct the Gmm with a dryback test procedure or by applying a dryback correction factor if aggregates have a moisture absorption of > 2.0% (see next subsection). - Calculate the Gmm to three decimal places, Gmm for SMA requires averaging 2 samples. If one of the individual samples deviates by more than from each other, results are considered suspect and a new set of samples is to be measured Dryback Procedure (Corrected Gmm) for Absorptive Aggregates (AASHTO T 209, Supplemental Procedure for Porous Aggregates) - Run a dryback procedure on Day 1-Sample 1, and determine a dryback correction factor for that test. Average the test dryback correction factor with the design JMF dryback correction factor and apply to the test data for a new Gmm. If the new average correction factor changes the Gmm by less than then use the design JMF dryback correction factor until otherwise determined by additional testing. NOT FOR CONTRACT ADMINISTRATION - Run a dryback procedure every other day of production on the first test sample, or any time there is a change in binder content greater than 0.1%, or a change in component blend percentages greater than 10% (or 20% combined), using the same averaging method as above to validate the original design JMF dryback correction factor. - If any average dryback correction factor changes the Gmm by more than 0.010, check for math or testing error first, otherwise a new dryback correction factor must be established by running drybacks on the next three samples. Average the new dryback correction factors and establish that average as the new JMF dryback May 2017 Page 12

40 correction factor Air Voids (%Va) AASHTO T 269 CMM 8-36 QMP - HMA The air void (%Va ) determination is a relationship between maximum specific gravity (Gmm) and bulk specific gravity (Gmb). Calculate to one decimal place Voids in Mineral Aggregate (VMA) VMA is calculated using the aggregate bulk specific gravity, Gsb, from the contractor mix design (unless a blend change has occurred in which case a new Gsb will be calculated), the asphalt content (Pb determined by CMM ), and the average SGC specimen bulk specific gravity, Gmb, as follows (calculate and record to 0.1.): 100 Pb = Ps (or % stone) Aggregate Effective Specific Gravity, (Gse) In the Gse calculation, the volume of the aggregate includes all the aggregate internal void spaces except those that absorb asphalt. Calculate and record to three decimal places (0.001). Where: - Gmm = end of previous days average. - Pb = end of previous days tank stick. - Gb = binder specific gravity from the mix design. Calculate this Gse at the beginning of each day and use that value for current day s calculations. If there is a change in binder content then recalculate a new Gse with the next available sample (consider it being nonrandom) and average with the previous Gse: Where: - Gmm = current sample test result. - Pb = reflecting the intended change (assumed). - Gb = from the mix design. A change in binder source or grade requires a check of the Gb Percent of Asphalt Content (Pb) Option is to use a plant gauge reading method and record and chart the Pb reading as close to representing the sample as possible. When calculating the Pb (an additional option for record and charting) use the following equation: NOT FOR CONTRACT ADMINISTRATION Where: - Gmm = current sample test result. - Gse = previous day. - Gb = mix design. Pb method selected should be used consistently to chart and calculate any related mixture properties for May 2017 Page 13

41 CMM 8-36 QMP - HMA project. Plant gauge readings may involve a calibration procedure and use of a correction/correlation factor Additional Formulas and Example Calculations 1. Determining the asphalt absorption, Pba, for the following: Given: Gse = Gsb = Gb = Determining the effective asphalt content, Pbe, of the asphaltic mixture for the following: Given: Pb = 5.3 Pba = 0.8 Ps = Determining the percent voids filled with asphalt (VFA) for the following compacted mixture: Given: VMA = 14.4 Va = Determining the dust to binder ratio (or DP: Dust Proportion): Given: Pbe = 4.5 % passing = Field Adjusted JMF The JMF may be adjusted in the field based on production test results see CMM When the JMF asphalt content is changed by 0.2% or more start new running average for Gmm. The compaction target maximum density for the day of the target change can be calculated using the most recent Gse and percent asphalt binder (Pb) for the new JMF and Gb (binder specific gravity) at 77 F from the mix design. NOT FOR CONTRACT ADMINISTRATION Job Mix Formula (JMF) Changes A JMF target binder content decrease exceeding 0.1% from the original JMF target will require a new mix design. Changing the contract specified PG requires compliance with CMM and the project engineer s approval. Addition of an additive to a JMF, except approved compaction aids, will require an approved JMF change. Changes of an additive identified on a JMF, or the dosing rate, will require an approved JMF change. Elimination or addition of any aggregate component requires a new mix design. Changes to the design aggregate component blend percentages are limited to 20% in combination. (See number 3). No JMF change requests are to occur prior to completion of three individual production tests. Data from prior production testing do not have to be from state projects, but must be sampled and tested by HTCP certified May 2017 Page 14

42 CMM 8-36 QMP - HMA personnel. Testing must occur in a WisDOT approved laboratory, following WisDOT approved methods. When making a Request for JMF Change, all laboratory results shall be submitted (electronically) to substantiate the use of materials from non-wisdot projects. The contractor will notify the project engineer of the proposed change using the "Request for JMF Change" form (Figure 10). Comments must include the sample test number indicating when the change is to become effective. Production adjustments and Requests for JMF Change submittals may not cause any target value to violate design requirements. Production tolerances may exceed those targets. The requested change may become effective up to four individual tests before the request was formally made. Documentation (electronic) that the contractor and project engineer had discussed a possible JMF Change must exist for the change to occur at a point prior to the test number on the formal request. Further changes will not be allowed until six additional individual test points, according to the normal sampling frequency, for the affected mix property have been documented. Each JMF sieve will be considered as an individual mix property. Control chart(s) for the affected property(ies) will accompany the "Request for JMF Change" (Figure 10) Field TSR Tests The tensile strength ratio is determined according to the procedures in AASTHO T 283 (without freeze-thaw conditioning cycles). After manufacturing the specimens at the plant, they may be tested in an offsite laboratory. Use distilled water for saturating and soaking the test specimens RAM Stockpile Samples The minimum test sample size must be determined from extracted aggregate gradation size per AASHTO T164. That has been divided into aggregate gradation numbers as follows: Nominal Max Size (mm) Minimum Weight of Test Sample (grams) # # # # When test results indicate that a change has occurred in the RAM asphalt content, a change in the design RAM asphalt percentage may be requested by the contractor or the project engineer. The request will include at least two recent RAM extractions and also identify all applicable mix designs to be affected. For each affected mix design a new Pbr (Percent binder replacement will be calculated and reported). The requested change will be reviewed for the department by an HTCP Certified HMA Technician at a level recognized for mix design, and a revised JMF can be issued HMA Quality Management Program Documentation The contractor is responsible for documenting all observations, records of inspection, and test results on a daily basis. Results of observations and records of inspection must be noted as they occur in a permanent field record. The testing records and control charts must be available in the QC laboratory at the asphalt plant. The contractor must maintain standardized control charts. Test results obtained by the contractor must be recorded on the control charts the same day the tests are conducted. The aggregate gradation test data must be recorded on the standardized control charts for all randomly selected production samples tested. Sieve sizes for aggregate gradation tests must include the maximum aggregate sieve size, the NMAS sieve, and any following sieves falling below: 1" (25.0mm), 3/4"(19.0mm), 1/2"(12.5mm), 3/8"(9.5mm), # 4 (4.75mm), #8(2.36mm), # 16 (1.18mm), # 30 (600μm), # 50 (300μm) # 100 (150μm) and # 200(75μm). NOT FOR CONTRACT ADMINISTRATION Documentation QC Records In addition to the requirements of the Records subsection of the standard specification, the contractor must provide: - A cumulative tonnage value to the project engineer on a daily basis. - Random number generation results and associated tonnage for QMP sampling - Binder Inventories (inclusive of incremental tonnages used to calculate binder usage for test samples and documentation validating calibration checks) May 2017 Page 15

43 CMM 8-36 QMP - HMA - When submitting charts and running average calculation sheets the contractor mix design ID and WisDOT 250 report number must be included on each sheet. Full name of qualified sampler, tester and qualified lab locations should be on individual sample test property worksheets. - Blend change history - Individual sample test property worksheets (Note: More detailed information may be requested or observed during actual production for evaluation purposes. In order to verify compliance with appropriate test procedure requirements, this information needs to be made available during that on-site evaluation). Records should be the original (handwritten or electronic) documents. However, the original source documents should be maintained in the project records. If the data is entered directly into an electronic document then that is acceptable as the source document. If the original document is handwritten and then transferred to an electronic document, the original handwritten document should be maintained as the source document. When supplying the original "source" document, a scanned copy is acceptable. Electronic documents are considered to be acceptable during construction, but the original documents need to be submitted after project completion for final project closeout QV Records Results of QV testing are posted to the appropriate QC charts for air voids and VMA and represented with a unique symbol (e.g.: red "X") Quality Verification Program Monitoring Contractor QMP Preconstruction The QV team is responsible for obtaining the following information: - Obtain WisDOT test number of the quality test report for the aggregate source being used. If source quality testing hasn t been completed, notify the department s Bureau of Technical Services laboratory. - Obtain the WisDOT test number of the mix design intended for use or a copy of the contractor's mix design, the review report, if available, from department s Materials Tracking system, and any contract special provisions. - Verify that the QC team personnel have the proper certifications. - Verify that the QC Laboratory facility is WisDOT qualified and has the equipment required by the QMP specification (inclusive of communication devices). Review any procedures for determining reheat correction factors and for the Gmm dry back correction factor (if applicable). Discuss any necessary calibrations, or pending recalibrations, for the gyratory compactor and what procedure will be used During Production During production, the QV team should, as often as they feel necessary: 1. Random Sampling: - Check the QC procedures for proper random number generation for all samples. - Verify the QC team is aware they are not to inform the plant before the random sampling will occur. 2. Samples: - Ensure all required samples are being taken for mixture properties and blended aggregate gradations. - Ensure that proper sampling and splitting procedures are being used and the field sample size is large enough to accomplish required testing. - Ensure that stockpile samples are taken and tested for reclaimed asphaltic pavement (RAP) when applicable. - Ensure tensile strength ratio (TSR) tests have been conducted at proper intervals when using anti-stripping agents. - Ensure that the retained samples (mix and blended aggregate) are properly labeled and stored in a dry protected area. 3. Testing: - Observe the reduction of the field samples to test size. - Observe the testing procedures paying attention to temperature of test samples before compaction, compaction efforts, times allotted between tasks, dry backs, etc. NOT FOR CONTRACT ADMINISTRATION May 2017 Page 16

44 CMM 8-36 QMP - HMA - Review data calculations. 4. Control charts: - Check to see that required control charts are present and up to date. - Check to see that control limits and warning bands are accurately drawn. - Check to see that the proper values are being plotted correctly. 5. Documentation: - Check to see that records of compliance are being documented and are up to date. - Check to see that adjustments to mixtures and JMF changes are noted on field records. - Check to see that records have been provided to the QV team on a daily basis Verification Sampling Product quality verification sampling is the responsibility of the department s QV team Plant Sampling Samples from the truck box will be taken by a member of the contractor QC team, and directly observed by the QV team member. In addition, if the initial split (QV / QV-retained) is performed by the contractor, it is also to be directly observed by the QV team member. The QV team will determine and document the random sampling procedure employed for mixture verification samples. Any or all of the following methods may be used: - Production tonnage. - Specific week during production. - Specific day-of-the-week during production. - Time-of-day. If some other method is used, it should be mutually agreed upon between the QV and QC teams and documented before taking place. The contract language specifies two mixture production days after the sample has been obtained by the contractor as the time within which the QV personnel must respond to the QC team relative to the agreement of data results. The intent is to provide information and feedback to the QC team as soon as practical in case there is data disagreement and the potential need to stop mix production. If the QV mixture sample temperature is 230 degrees F or higher when delivered to the testing facility, quartering may start immediately. If the temperature is below 230F, place in a 300F oven, until workable for quartering, but not to exceed two hours. Microwaves are not to be used to reheat an HMA sample Determining Acceptable Verification Parameters Whenever a flag has been raised by disagreement of QV test results with the defined acceptable parameters, immediate investigation will occur using additional testing, troubleshooting, and dispute resolution actions Additional Testing WisDOT s Bureau of Technical Services laboratory is to test QV-retained and any needed forward and backward QC-retained samples. Example 4 A QV sample taken following QC test 5-3, falls outside of 2.0 to 4.3% air voids (3.2 to 5.8% for SMA). The WisDOT BTS lab tests retained portion of QV sample, along with QC-ret sample 5-3 and QC-ret 5-4 once available. The Bureau continues testing of retained samples both forward and back until a test result in each direction meets criteria for 75% pay in accordance with Figure 8 (i.e., 1.8 to 4.6% air voids, or 2.9 to 6.1% for SMA). If criteria has not been met and no further QC-retained sample exists in a given direction, then liability for that mixture may include back to production start-up/end or QV sample. NOT FOR CONTRACT ADMINISTRATION BTS is to provide QC retained split sample testing on the nearest forward QC sample as soon as practical, and continue until the QC-retained split sample is % air voids and (2.9 to 6.1% for SMA) and within 0.7% minimum VMA. In addition, when the QV team is back on the site to obtain the additional QC-retained samples, another QV sample will be taken. May 2017 Page 17

45 CMM 8-36 QMP - HMA Example 5 The QV sample taken following QC test 5-3, falls outside acceptable parameters. The QV team returns to the plant site on day 7 and obtains any QC-ret samples forward of sample 5-4 available at that time (to be sent to the WisDOT-BTS lab), and directs a new QV sample be taken representing day Troubleshooting The following points are to be considered and re-checked: - Calculations. - QC data trends. - Equipment calibration records. - Sampling and splitting observations/notes. - Proper use of re-heat correction factors. If a or greater variability exists between QC and reheated samples (matching QC-retained portion), then a Gmb Reheat Correction Factor is to be determined to aid in troubleshooting. Gmb Reheat Correction Factor (Calc d to 0.001) = Gmb (Un-reheated) / Gmb (Reheated) Then apply the correction factor to the reheated sample by: Corr Gmb = Gmb (Reheated) When comparing the uncorrected Gmb to the corrected Gmb, if the difference is less than 0.005, then the correction factor will not be used. If a or greater variability exists between QC and reheated samples (matching QC-retained portion), then a Gmm reheat correction factor is to be determined to aid in troubleshooting. It should be calculated to Gmm Reheat Correction Factor = Gmm (Un-reheated) / Gmm (Reheated) - Then apply the correction factor to the reheated sample: Corrected Gmm = Gmm (reheated) * correction factor. - When comparing the uncorrected Gmm to the corrected Gmm, if the difference is less than 0.005, then the correction factor will not be used Dispute Resolution For the test results of the QV retained portion, the contract language specifies two working days after receipt of the sample. The receipt day refers to receipt of the sample at the department s Bureau of Technical Services AASHTO accredited laboratory. The intent is to provide test information and feedback to the QC/QV team as soon as practical and targeting within 7 working days of the date of the QV sample. At the completion of dispute resolution testing (QV-ret and required backward and forward QC-ret) the WisDOT - Bureau of Technical Services AASHTO accredited laboratory personnel dealing with asphalt mix designs will determine and recommend a range of non-compliant tons based on the following information: - Gmm & Gmb as measured by BTS - Air Voids as calculated from BTS volumetric data - VMA of QC/QV-ret samples tested by BTS In determining unacceptable or non-compliant materials, the department s Bureau of Technical Services AASHTO accredited laboratory personnel dealing with asphalt mix designs will provide documentation to the QV team recommending tonnages to be affected. A standard recommendation will be assessed based on the following requirements: NOT FOR CONTRACT ADMINISTRATION - Va is within a range of 1.9 to 4.4 percent (i.e., 90 to 100% pay in accordance with Figure8) for HMA. - Va is within a range of 3.1 to 5.9 percent (i.e., 90 to 100% pay) for SMA. - VMA is within minus 0.5 of the minimum requirement for the mix design nominal maximum aggregate size. The general process flow chart for dispute resolution is shown in Figure 8. Example scenarios are provided in Figure 9 (based on HMA requirements). In the event that the range of affected tonnage is determined to be at May 2017 Page 18

46 CMM 8-36 QMP - HMA the QV (isolated problem), a pay adjustment calculated to tonnage halfway between samples will be assessed. There is no intent to use multiple pay adjustments, but the lowest percent pay will supersede others. The QV team will further complete documentation responsibilities by determining the dollar amount for any affected mixture tonnage and will forward that information to appropriate project personnel and the QC team. Figure 10 is an example of a spreadsheet used to calculate pay adjustments. Figure 8 HMA Dispute Resolution Flow Chart Description Criteria Pay Factor High Air Voids Pay Factor 4.3% < Va < 5.0% = (Va - 4.3) * 71.4 Low Air Voids Pay Factor 1.5% < Va < 2.0% = 100 * [1 - (2.0 - Va)] Low VMA Pay Factor 0.5% < VMA below min < 1.0% = 100 * [1 - (percent below min )] SMA 100% pay requires: Va = %, and VMA > 0.5% below minimum. SMA 50% pay corresponds to: Va < 2.5% or > 6.5%, and VMA > 1.0% below minimum. SMA Prorated Pay Factors (between 50 and 100% pay) are as follows: Description Criteria Pay Factor High Air Voids Pay Factor 5.8% < Va < 6.5% = (Va 5.8) * 71.4 Low Air Voids Pay Factor 2.5% < Va < 3.2% = (3.2 Va) * 71.4 Low VMA Pay Factor 0.5% > VMA below min > 1.0% = 100 * [1 - (percent below min )] Footnotes: NOT FOR CONTRACT ADMINISTRATION 1. Pay of less than 100% on QV-retain test will result in additional testing of forward and back sample 2. Pay of less than 75% on forward or backward QC-retain will result in testing of the next forward or backward sample 3. Pay of 50% may result in remove and replace instead of accepting at 50% pay. May 2017 Page 19

47 CMM 8-36 QMP - HMA Figure 9 HMA Verification Dispute Resolution Scenarios NOT FOR CONTRACT ADMINISTRATION May 2017 Page 20

48 CMM 8-36 QMP - HMA Figure 9 Example of HMA Verification Dispute Resolution Scenarios (cont'd) Figure 10 Adjustment Calculation Example Project ID: xxxx-xx-xx MIX TYPE: 4 MT xx-xx S MTS Record: Recommended Adjustments x xx-20xx % Pay SS Affected Mix Tons Mix Bid Price TOTAL Adjustment (w/h) Air Void Failure 50% 25.0 $ $ VMA Failure 75% 0.0 $ $ Comment: Alternate/Final Adjustments % Pay SS Affected Mix Tons Mix Bid Price NOT FOR CONTRACT ADMINISTRATION $ TOTAL Adjustment (w/h) Air Void Failure 50% 25.0 $ $ VMA Failure 75% 0.0 $ $ REMARKS: $ Footnote: 1. Contact Bureau of Technical Services, Materials Laboratory Unit 2 for further assistance. May 2017 Page 21

49 CMM 8-36 QMP - HMA Example Worksheet Figure 11 Request for JMF Change NOT FOR CONTRACT ADMINISTRATION May 2017 Page 22

50 TOPIC B: Specifications and Construction and Materials Manual Page B-2 Exercises on WisDOT Standard Specification Section Where would one find the aggregate master gradation requirements and production control limits? 2. In what instances are the contractor required to stop mixture production? 3. What payment reduction percentage is applied to air voids produced within the warning bands? 4. What is the maximum percent wear loss at 500 revolutions for an MT mixture? 5. What is the minimum FAA requirement for an HT mixture? 6. What is the minimum percent VMA for a #4 gradation (12.5 mm) HT mixture? 7. What is the acceptable range for fine aggregates passing the 75 micron sieve (#200) in a #3 gradation (19.0 mm) mix?

51 TOPIC C: Asphaltic Mix Design

52 TOPIC C: Asphaltic Mix Design Page C-1 Purpose of Asphalt Mix Design The purpose of the mix design is to determine the optimum asphalt content for a specific blend of aggregates to satisfy a given set of specification parameters. The goal of asphalt mix design is to produce an asphalt pavement with specific desirable characteristics. Those characteristics include workability, stability, durability, impermeability, flexibility, fatigue resistance, rut resistance, and skid resistance. Laboratory Design versus Field Production The laboratory mix design system is in place to determine the correct proportions of asphalt cement and aggregate required to produce an asphalt mix with the properties and characteristics needed to withstand the effects of traffic and the environment for many years. Mix design is performed in the laboratory using the Superpave method. This laboratory procedure is created to simulate and predict the effects of traffic on the materials selected. Until the late 1990's, the most common mix design method was the Marshall method, used by about 75 percent of state highway departments, as well as by the U.S. Department of Defense and the Federal Aviation Administration. By the mid-1990's state departments of transportation began to implement the Superpave (Superior Performing Asphalt Pavement) method of mix design, also developed under SHRP. While laboratory procedures are developed and used for their predictive capabilities, mixture properties and characteristics may differ between laboratory-produced mixes and plantproduced mixes. (Refer to Figure 5.1, table) Asphalt Mix Design and Job Mix Formula At the conclusion of the laboratory work involved in developing the asphalt mix design, the designer s recommended aggregate structure, the optimum amount of asphaltic binder and its associated mix properties are often referred to as the Job Mix Formula (JMF). The Mix Design Report is documentation of the laboratory evaluation performed while selecting the aggregate structure and asphalt content to be used. The selected material recommendations are then reviewed for meeting specification requirements. The mix design report requirements are specified in WisDOT CMM 8-66 Standard Method of Asphaltic Mix Design. This report is also a handy tool for mixture troubleshooting in the field.

53 TOPIC C: Asphaltic Mix Design Page C-2 While the complete mix design contains greater detail about the materials, test trials and completed trial results, the job mix formula provides the actual target values intended for field production. The JMF targets also indicate the baseline values for applying specification tolerance bands in order for the producer to track and maintain quality control.

54 TOPIC C: Asphaltic Mix Design Page C-3 Figure 5.1

55 TOPIC C: Asphaltic Mix Design Page C-4 Figure 5.2 Example Asphalt Mix Design Report

56 TOPIC C: Asphaltic Mix Design Page C-5 Maximum Density Line Relationship The maximum density line is a tool used to analyze and evaluate relationships between the JMF gradation and the voids in mineral aggregates (VMA). A mixture on top of the maximum density line is finer, and inversely, a mixture below the maximum density line is coarser. The VMA will increase as the gradation moves further from the maximum density line whether coarser or finer. The distance on either side of the maximum density line is controlled by the aggregate gradation master range or JMF limits. Most of VMA is determined on the finer end of the grading band. If VMA (goes up) = VTM (goes up), then VMA (goes down) = VTM (goes down) Caution, sometimes a sand or camel hump on the JMF gradation blend may appear at or near the No. 30 sieve. The sand or camel hump at the No. 30 sieve will make an asphaltic mixture very difficult to lay down and place and also may attribute to a tender asphaltic mixture. The sand or camel hump is usually caused by the use of natural river sands. The natural river sands are mostly one-sized particles, which attribute to problems on the No. 30 sieve.

57 TOPIC C: Asphaltic Mix Design Page C-6 VMA, Voids in the Mineral Aggregate Voids in the mineral aggregate (VMA) is the volume of intergranular void space between the aggregate particles of a compacted paving mixture that includes the air voids and the effective asphalt content, expressed as a percent of the total volume of the sample. The purpose of the VMA criteria is to allow enough space for the asphalt in the mixture to provide durability in the asphalt pavement.

58 TOPIC C: Asphaltic Mix Design Page C-7

59 TOPIC C: Asphaltic Mix Design Page C-8

60 TOPIC C: Asphaltic Mix Design Page C-9 Test Property Curves for HMA A Certified Asphalt Technician TPC must be able to analyze and interpret test property curves associated with the HMA design method used. The test property curves are established as best fit graphical plots, and analyzed in relation to the optimum asphalt binder content chosen. Once the optimum binder content is chosen to meet the air void requirement, then all other properties are checked against the specification requirements for compliance. Selection of Design Asphalt Binder Content Using Test Property Curves V a VMA VFA % binder Blend 3 DP %% binder % binder % binder %G mm at N ini %G mm at N max % binder % binder 1 The plotted data also provides additional predictive information useful when considering making changes to the mixture. Regarding the bottom 2 sketches, % Gmm at Nini and % Gmm at Nmax, these properties are actually measured at optimum binder content.

61 TOPIC C: Asphaltic Mix Design Page C-10 Selection of Percent Asphalt Content From the Air Voids Data The design percent AC is selected by knowing the specified Voids in the Total Mixture (VTM) requirement for the type of mixture being produced. The VTM requirement for WisDOT mixtures is 4.0 percent so the designer can go to the air void graph and find the point representing 4.0% air voids, then move across the graph to the intersecting point on the air voids curve and drop to the bottom of the chart to select the percent asphalt content. (NOTE: for regressed air void mixtures, a similar procedure is used, however, the optimum percent asphalt content should be selected by moving across the graph to the intersecting point of 3.0% air voids.) In the example below, the percent AC (or percent binder, Pb) would be 5.5%. Selection of Percent Asphalt Content Satisfying All Design Criteria The percent AC selected for this 4 MT (12.5 mm) mixture is 5.5 percent. All of the calculated and measured asphaltic mixture properties at this asphalt content are evaluated by comparing them to the specified mix design criteria, for example: Asphalt Mix Design Data WisDOT HMA Mix Design at Optimum A.C. Content = 5.5% Requirements VTM or Air Voids (%) = OK VMA (%) = min. OK VFB (%) = OK Th. Max. Sp. Cr. = NA Bulk Sp. Gr. = NA Tensile Strength Ratio = min. OK Recommended Mixing Temp = 275 F -300 F Dust to Asphalt Ratio = OK This MT asphalt mix design satisfies all WisDOT requirements for this type of mixture.

62 TOPIC C: Asphaltic Mix Design Page C-11 Dust to Binder Ratio The dust to binder ratio indicates, between 0.6 and 1.2, the most economical proportion to economize asphalt cement in the mixture. An asphalt mix designer is wasting asphalt cement in the mixture if no P-200 mesh material is added, and again, the opposite is true if too much asphalt cement is added. The dust to binder ratio is calculated as follows, using the effective binder content (Pbe) JMF P-200 = 4.9 JMF Pb = 5.5 Pbe = 5.2 (accounts for the absorbed binder) Dust Proportion = P200/Pbe = 4.9/5.2 = 0.9 Increase of P-200 During Mix Design Some asphalt mix designers like to increase the P-200 by some percentage to compensate for anticipated degradation in dryer/drum mixer during production. Be careful when conducting your gradation analysis to use the original P-200 percentage when sampling aggregates off the conveyor belt or stockpile. Anytime you are performing WisDOT extractions (CMM 8-36), make sure your P-200 value is referenced from the asphalt mix design report for plant produced mix JMF P-200. Typically P-200 is 1.0 to 1.5% higher in plant produced mix than would be expected from blended stock pile gradations due to aggregate degradation. What happens when the aggregates are conveyed into the dryer/drum mixer of an asphalt plant? At a batch plant, this unit is called a dryer, and at a drum mix plant, it is called a drum mixer. These units are necessary parts of the hot-mix operation for they dry and heat aggregates coming from the cold feed conveyor belts. Cold aggregate is fed into the upper end of the dryer/drum mixer and is picked up by steel angles or flights mounted on the inside of the drum. As the large dryer/drum mixer rotates, the aggregates are picked up by the flights and are dropped. During the drying process, degradation occurs to the aggregates, causing an increase in P-200 for plantmixed aggregate. The main reason for adding the additional percentage of P-200 during the asphalt mix design process is to avoid collapsing VMA and low air voids at project start-up.

63 TOPIC C: Asphaltic Mix Design Page C-12 Asphaltic Mix Design Review Process The asphaltic mix design must be submitted to WisDOT Bureau of Technical Services Asphalt Mix Design area before project start-up. A WisDOT Certified HMA-MD is responsible for the review. You can contact Jeff Anderson at the following address: Jeff Anderson, Certified HMATEC-MD WisDOT - Bureau Technical Services 3502 Kinsman Blvd. Madison, WI Phone: (608) Fax: (608) According to Laboratory Standard Method of Asphalt Mix Design, WisDOT CMM 8-66, the Asphalt Mix Design report shall be submitted to WisDOT Bureau of Technical Services Asphalt Mix Design along with a copy to the pertinent district office. Upon receipt of the report and any required material samples to the central office laboratory, a review will be completed and notification of specification compliance will be sent to the submitting lab. Further detail of the report submittal process is listed in the appendix (CMM 8-66).

64 TOPIC C: Asphaltic Mix Design Page C-13 Superpave Method of Mix Design Chapter Exercises 1. What is the most important factor in predicting asphaltic mixture performance? 2. What should the in-place air voids be for an HT mixture? 3. Air voids between and % after two to three years of traffic loading will provide optimum pavement performance. 4. The higher the FAA value, the higher the. References Hot Mix Asphalt Paving Handbook, US Army Corps of Engineers in conjunction with AASHTO, FAA, FHWA, NAPA, APEA, NACED Hot Mix Asphalt for the Undergraduate, FHWA-RD A Guide for Hot Mix Asphalt Pavement, TAS 30 - NAPA Mix Design Methods for Asphalt Concrete and Other Hot Mix Types, MS-2, Sixth edition, Asphalt Institute

65 1 TOPIC D: Aggregate Blending

66 TOPIC D: Aggregate Blending Page D-1 Aggregate Blending The HMA-TPC Technician will encounter nonuniform stockpile situations, which will require stockpile gradation JMF blends to be recalculated. Being able to compute new stockpile aggregate percentages to identify a new Job Mix Formula (JMF) blend is necessary for asphalt mixture property process control. Procedure for blending of two or more aggregate stockpiles is called the trial and error method. The trial and error method is accomplished by following the steps shown below: Step 1. Obtain a gradation analysis from each stockpile or cold feed bin. Samples may be procured from the stockpiles or cold feed bin conveyor belts. All sampling and testing procedures must conform to the prescribed specification methods. The gradation analysis results are only as representative as the sampling method. Step 2. SIEVE Obtain the specified JMF limits for each sieve from the aggregate gradation master range. The aggregate gradation master ranges are obtained from Wisconsin standard specification, Section as shown: No. 1 (37.5 mm) 50.0-mm 100 No. 2 (25.0 mm) 37.5-mm PERCENTS PASSING DESIGNATED SIEVES No.3 (19.0 mm) 25.0-mm 90 max NOMINAL SIZE No. 4 (12.5 mm) No. 5 (9.5 mm) SMA No. 4 (12.5 mm) 19.0-mm 90 max SMA No. 5 (9.5 mm) 12.5-mm 90 max mm 90 max mm 90 max mm µm % MINIMUM VMA [1] 15.0 [2] Enter the specified aggregate gradation master ranges in the upper and lower JMF limits for each specified sieve size in the left corner of the worksheet. Also, enter the specified aggregate gradation master range for the JMF limits in the lower right corner. (See Figure Blending Worksheet Example.) Step 3. Step 4. Select a target value. The goal of aggregate blending is to combine two or more aggregate stockpile sources to meet the specified JMF limits for each sieve. (See Figure Blending Worksheet Example.) Guess the proportion. A percent of each stockpile, incorporated into the asphaltic mixture, is guessed to try to satisfy all of the JMF limits. All of the guessed percentages relating to each stockpile must total 100 percent. (See Figure 6.1 Blending Worksheet Example.)

67 TOPIC D: Aggregate Blending Page D-2 SIEVE SIZE LOWER RANGE BLENDING WORKSHEET UPPER RANGE AGG #1 AGG #2 AGG #2 AGG #4 AGG # ¾ ½ / NO STEP 1 NO NO NO No NO NO STEP 4 SIEVE 50% 50% % % % % STEP 5 STEP 2 ¾ ½ 3/8 NO. 4 NO. 8 NO (.50)=50 100(.50)= = 100 = 100 ok (.50)= (.50)= = 83.9 = (.50)= (.50)= = 56.5 = 56.5 ok 90 max 2.2(.50) = (.50)= = 36.7 = 36.7 ok (.50)= (.50)= = 28.9 = 28.9 ok STEP 3 NO. 30 No. 50 NO. 100 NO (.50)= (.50)= = 3.6 = 3.6 ok 2-10 Figure 6.1 Blending Worksheet Example

68 TOPIC D: Aggregate Blending Page D-3 Step 5. Calculate the combined gradation. Each gradation must be multiplied by the guessed percentage to determine the new percentage value. Once the new percentage values have been calculated, each sieve row is added together to determine the new JMF blend. The trial and error method may become very tedious and time consuming. A time saving measure is to calculate two or three key sieves, such as 3/4, No. 8 and No If the combined key sieve aggregates satisfy the JMF limit requirements, then calculate the other sieves to see whether the combined aggregate blend does satisfy all other JMF limits. (See Figure 6.1- Blending Worksheet Example.) Step 6. If the combined aggregate blend does not satisfy all the JMF limit requirements, try again. (See Figure 6.1- Blending Worksheet Example.) Let s try an example: (See Figure Blending Worksheet Example.) Step 1. Step 2. MT Step 3. Obtain a gradation analysis from each stockpile or cold feed bin. Obtain the aggregate gradation master range specification limits for a #4 (12.5 mm) asphaltic mixture. Select a target value. Usually the target is midrange of the JMF specification limits. Step 4. Guess the proportions. Let s try aggregate #1-50% and aggregate #2-50%. Remember the sum of percents must total 100 percent (50% + 50% = 100%). Step 5. Calculate the combined gradation, for example: Sieve AGG#1 AGG#2 JMF Blend (50%) (50%) 3/4 100 x.50 = x.50 = = 100 No x.50 = x.50 = = 28.9 No x.50 = x.50 = = 3.6 Analyze all data to determine if the combined aggregate gradation meets the specified JMF limits. In the 50/50 blend, all sieves meet the JMF limit specification except the 1/2" sieve. Step 6. Try again. The combined aggregate blend does not satisfy all the JMF limit parameters. Repeat procedure with another guess. Example 2: Refer to Figure Blending Worksheet Example. Let s try AGG #1 = 20% and AGG #2 = 80%. The reasoning for the trial is because the 1/2" sieve was lower than the JMF specification limits. Raising the percent AGG #2 to 80 percent should increase the percent passing on the 1/2" sieve. Let s try once again. The combination of 20 percent AGG #1 and 80 percent AGG #2 does satisfy the combined aggregate gradation master band (See Figure Blending Worksheet Exercise.)

69 TOPIC D: Aggregate Blending Page D-4 BLENDING WORKSHEET STEP 6 SIEVE 20% 80% % % % % ¾ 100(.20)=20 100(.80)= = 100 = 100 ok 100 ½ 67.6(.20)= (.80)= = 93.5 = 93.5 ok /8 16.6(.20)= (.80)= = 80.3 = 80.3 ok 90 max NO (.20)= (.80)= = 57.4 = 57.4 ok NO (.20)= (.80)= = 45.0 = 45.0 ok NO. 16 NO. 30 No. 50 NO. 100 NO (.20)= (.80)= = 4.8 = 4.8 ok 2-10 SIEVE % % % % % % ¾ ½ 3/8 NO. 4 NO. 8 NO. 16 NO. 30 No. 50 NO. 100 NO. 200 Figure 6.2 Blending Worksheet Example

70 TOPIC D: Aggregate Blending Page D-5

71 TOPIC D: Aggregate Blending Page D-6 Federal Highway Administration (FHWA) 0.45 Power Chart The FHWA 0.45 power chart is used to plot and evaluate a gradation analysis. The FHWA 0.45 power chart is a very useful tool for evaluating the aggregate gradation versus voids in mineral aggregate (VMA) property. The upper and lower JMF specification limits for the specified aggregate gradation, combined or single aggregate gradation, and the maximum density line shall be plotted on the FHWA 0.45 power chart. (See Figure FHWA 0.45 Power Chart.) Maximum Density Line The maximum density line in Wisconsin is a straight line plotted from the origin through the first (i.e., largest) sieve which has material retained. For example, in Figure FHWA 0.45 Power Chart, the 1/2" sieve is identified as the first sieve having material retained. The maximum density line is drawn from 0.0 origin through the 1/2" sieve at 93.5 percent. (The maximum density curve drawn through the actual percent passing at the nominal maximum sieve has proven effective in evaluating many Wisconsin mix designs.)

72 TOPIC D: Aggregate Blending Page D-7 Figure 6.3 Federal Highway Administration (FWA) 0.45 Power Chart

73 TOPIC D: Aggregate Blending Page D-8 AGGREGATE BLENDING EXERCISES 1. Combine three (3) aggregates to meet a gradation specification. Refer to Figures 6.4 and Blending Worksheet Problem for JMF blending of three aggregates. 2. Combine four (4) aggregates to meet a gradation specification. Refer to Figures 6.5, and Blending Worksheet Problem for JMF blending of four aggregates. The aggregate gradation master ranges are obtained from Wisconsin Standard Specification, as shown: SIEVE No. 1 (37.5 mm) 50.0-mm 100 No. 2 (25.0 mm) 37.5-mm PERCENTS PASSING DESIGNATED SIEVES No.3 (19.0 mm) 25.0-mm 90 max NOMINAL SIZE No. 4 (12.5 mm) No. 5 (9.5 mm) SMA No. 4 (12.5 mm) 19.0-mm 90 max SMA No. 5 (9.5 mm) 12.5-mm 90 max mm 90 max mm 90 max mm µm % MINIMUM VMA [1] 15.0 [2] FHWA 0.45 POWER CHART EXERCISES 1. Use the results of aggregate blending problem # 1 to plot the maximum density line, JMF limits, and gradation analysis on an FHWA 0.45 Power Chart. Refer to Figure 6.6 FHWA 0.45 Power Chart to plot the data. 2. Use the results of aggregate blending problem # 2 to plot the maximum density line, JMF limits, and gradation analysis on an FHWA 0.45 Power Chart. Refer to Figure 6.7 FHWA 0.45 Power Chart to plot the data.

74 TOPIC D: Aggregate Blending Page D-9 SIEVE SIZE LOWER RANGE UPPER RANGE AGG #1 AGG #2 AGG #3 AGG #4 AGG # ¾ ½ / NO NO NO NO No NO NO SIEVE % % % % % % ¾ ½ 3/8 NO. 4 NO. 8 NO. 16 NO. 30 No. 50 NO. 100 NO. 200 Figure 6.4 Blending Worksheet Problem

75 TOPIC D: Aggregate Blending Page D-10 SIEVE BLENDING WORKSHEET % % % % % % ¾ ½ 3/8 NO. 4 NO. 8 NO. 16 NO. 30 No. 50 NO. 100 NO. 200 SIEVE % % % % % % ¾ ½ 3/8 NO. 4 NO. 8 NO. 16 NO. 30 No. 50 NO. 100 NO. 200 Figure Blending Worksheet Problem

76 TOPIC D: Aggregate Blending Page D-11 SIEVE SIZE LOWER RANGE UPPER RANGE AGG #1 AGG #2 AGG #3 AGG #4 AGG # ¾ ½ / NO NO NO NO No NO NO SIEVE % % % % % % ¾ ½ 3/8 NO. 4 NO. 8 NO. 16 NO. 30 No. 50 NO. 100 NO. 200 Figure 6.5 Blending Worksheet Problem

77 TOPIC D: Aggregate Blending Page D-12 SIEVE % % % % % % ¾ ½ 3/8 NO. 4 NO. 8 NO. 16 NO. 30 No. 50 NO. 100 NO. 200 SIEVE % % % % % % ¾ ½ 3/8 NO. 4 NO. 8 NO. 16 NO. 30 No. 50 NO. 100 NO. 200 Figure Blending Worksheet Problem

78 TOPIC D: Aggregate Blending Page D-13 SIEVE BLENDING WORKSHEET % % % % % % ¾ ½ 3/8 NO. 4 NO. 8 NO. 16 NO. 30 No. 50 NO. 100 NO. 200 SIEVE % % % % % % ¾ ½ 3/8 NO. 4 NO. 8 NO. 16 NO. 30 No. 50 NO. 100 NO. 200 Figure Blending Worksheet Problem

79 TOPIC D: Aggregate Blending Page D-14 Figure 6.6 FHWA 0.45 Power Chart

80 TOPIC D: Aggregate Blending Page D-15 Figure 6.7 FHWA 0.45 Power Chart

81 TOPIC E: Quality Control Organizational Plan

82 TOPIC E: Quality Control Organizational Plan Page E-1 Quality Control Organization Plan According to the Quality Management Program, Asphaltic Mixture, the contractor shall provide and maintain a quality control program. The quality control program is defined as all activities, including mix design, process control inspection, sampling and testing, and necessary adjustments in the process that are related to the production and placement of a hot mix asphaltic pavement which meets the requirements of the specification. Shown below is an example of a quality plan: EXAMPLE QUALITY CONTROL PLAN Crushed Aggregate and Hot Mix Asphalt Project #: Project Location: County: Construction Supervisor: Project Engineer: Type of Work: Project Foreman: OCP Prepared by: THE COMMUNICATION LINK Telephone Company Fax Permanent Lab Telephone Permanent Lab Fax Project Foreman, Mobile & Pager Mobile & Portable Lab Telephone & Fax

83 TOPIC E: Quality Control Organizational Plan Page E-2 HTCP CERTIFIED PERSONNEL THE PRIMARY QUALITY CONTROL PERSONNEL THAT WILL BE WORKING ON THIS PROJECT Name Responsibilities Certified AGGTEC-I, HMA-IPT, HMA- Will be overseeing the general operation of the TPC, HMA-MD lab. Certified AGGTEC-I, AGGTEC-II, Will be overseeing the hot mix asphalt design HMA-IPT, HMA-TPC, HMA-MD and testing for this project Certified AGGTEC-I, HMA-IPT, HMA- Will be the primary laboratory technician for TPC, NUCDENSITYTEC-1 this project. Will be performing aggregate production and placement samples, as well as the hot mix asphalt testing for this project. Will be certified AGGTEC- I in May and may perform aggregate sampling and testing work Certified TRANSPORTATION MATERIAL SAMPLING Certified AGGTEC-I Certified AGGTEC-I, HMA-IPT, HMA- TPC, PROFILOGRAPH, NUCDENSITYTEC-1 Certified NUCDENSITYTEC-1 Certified NUCDENSITYTEC-1, PROFILER on this project. Aggregate plant operator and performs stockpile sampling during aggregate production. Aggregate plant operator and performs stockpile sampling during aggregate production. All laboratory personnel that may be working on this project have direct and open communication with each other, plant personnel, road crews, and company representatives through the project. LABORATORY AND EQUIPMENT REQUIREMENTS The permanent and portable laboratories are certified according to the Wisconsin Qualified Laboratory Program. The Quality Manual is available in the lab.

84 TOPIC E: Quality Control Organizational Plan Page E-3 During aggregate production and the hot mix asphalt design process, the laboratory facility used for testing will be the permanent laboratory facility. The lab is located. During hot mix asphalt placement, the laboratory facility used for testing will be the portable laboratory facility. The lab will be located, along with the Hot Plant, at Pit. The Pit is located on Road in the Town or City of. Aggregate placement testing will be performed at the laboratory we are working in at the time aggregate is being placed, either the permanent or portable laboratory. WisDOT personnel will be notified of which lab we will be working out of at that time. Retained samples, quality control charts, and process documentation will be maintained at the laboratory being worked in at that time. Control charts and testing documentation will be updated and completed daily. Laboratory equipment will be calibrated and inspected according to WisDOT and QMP procedures and/or by manufacturer s recommendations. All records are maintained in the Quality Manual, which is located in the lab. Equipment such as scales, sieves, and thermometers will be inspected daily for excess wear and/or damage. Before startup in the portable laboratory, the laboratory shall be leveled, the Superpave Gyratory Compactor shall be calibrated, and scales shall be checked with the weight set. Records shall be kept for these procedures and maintained in the Quality Manual. All sampling and testing procedures will be performed according to the Quality Management Procedural Manual and other WisDOT specifications and project documents. Stockpile sampling of aggregates will be performed during the aggregate production. HOT MIX ASPHALT DESIGN This project requires a 12.5mm Superpave design and a 19.0mm Superpave design. The hot mix asphalt designs are not completed at this time. The designs will be started approximately, on the completion of the designs and approval by WisDOT Central Office; they will forward them to appropriate WisDOT District project. SOURCE #1 AGGREGATE SOURCES SOURCE #2

85 TOPIC E: Quality Control Organizational Plan Page E-4 SOURCE STUDIES: Pit has been determined to be satisfactory according to WisDOT test number. (soundness = 0.4%, wear = 2.75%, 13.0%) Pit has been determined to be satisfactory according to WisDOT test number. (soundness = 1.0%, wear = 4.1%, 18.3%) PROCESS CONTROL INSPECTION AND ADJUSTMENT AGGREGATE PRODUCTION PLANT The aggregate production plant operator and crew perform control inspection of the crushing equipment and site on a daily basis. This includes inspecting the general condition of the equipment, adjusting the jaw and cone settings, observing screen conditions, monitoring fugitive dust control and site appearance, and observing changes in the raw material and in stockpiling conditions. Aggregate process adjustments may include screen changes, jaw and cone setting adjustments, and addition or rejection of sand. Process adjustments will be made according to results obtained from laboratory analyses. HOT MIX ASPHALT PLANT The hot plant operator and crew perform control inspection of the hot plant equipment and site on a daily basis. This includes inspecting the general condition of equipment, inspecting the drum end seals and ductwork, and calibrating the asphalt and aggregates zero and span scales. Hot mix asphalt process adjustments may include gradation changes, moisture changes, and % asphalt cement changes. Process adjustments will be determined by laboratory analyses and recorded by laboratory personnel. LABORATORY The on-site laboratory includes a water supply, electrical power, telephone, fax, and all of the necessary equipment and supplies to perform quality control testing as specified in the QMP provisions. Laboratory technicians perform control inspection of laboratory equipment on a daily basis. This includes inspecting the general condition of equipment, performing maintenance and calibrations, if necessary, maintaining quality control charts and process documentation, and maintaining open communication with project personnel.

86 TOPIC E: Quality Control Organizational Plan Page E-5 WisDOT standard specification, Personnel Requirements, specifically states under Contractor s Quality Control that the contractor shall have an HMA-TPC Technician available to make any necessary process adjustments. An organizational chart, including names, telephone numbers, and current certification of all those responsible for the quality control program shall be posted in the contractor s laboratory prior to the beginning of asphaltic mixture production. This chart shall be updated with appropriate changes as they become available!! See an example of a completed Quality Control Organizational Chart in Figure 4.1 An example of the Quality Control Organizational Chart has been provided for your company s use - See Figure 4.2. The quality control organizational plan, required by WisDOT specification, will be one of your most important communication tools. The quality control organizational plan will be the first step in developing a quality control team. The first section of the quality control organizational plan must list actual personnel working on the specific project or job. For instance, the first section of the list must include names of the certified technicians, along with their level of pertinent certification and expiration dates, plant foreman, paving foreman, and project manager. The second section of the chart may include the company s regional manager(s). The third section of the chart may involve corporate personnel, such as vice president, quality control manager, and HMA-MD certified people. Finally, the last portion of the chart may include a list of certified QV personnel, the project engineer, and the construction supervisor. Remember, the whole concept of QC/QV revolves around the aspect of partnering. As an HMA- TPC Technician, you have a responsibility to communicate with the QC/QV teams as a start to the decision-making process. It is a very good idea before project start-up to schedule a preconstruction meeting to begin positive open communication channels between the QC and QV teams. Open communication channels are essential to every QC/QV project relationship. Usually an HMA-TPC Technician is responsible for multiple projects, so make sure you carry a copy of each organization s quality control plan for each specific project. For instance, a problem may arise, and you may be able to solve the particular instance by phone or . Sometimes it is possible to troubleshoot a project using to analyze the data without ever actually visiting the plant site. Again, COMMUNICATION will aid you in process control troubleshooting decisions.

87 TOPIC E: Quality Control Organizational Plan Page E-6 Request for Job Mix Formula Change The JMF represents the control limits on a control chart. Each specified sieve is regulated by JMF tolerances. Refer to WisDOT Standard Specifications, Section , for the actual JMF tolerances. Job Mix Formula Adjustment A request for a job mix formula adjustment may be made to the engineer by the contractor. The requested change will be reviewed by the WisDOT department HMA-MD Technician. If acceptable, a revised job mix formula shall be issued. The number of adjustments will be limited according to the current WisDOT department policy. Adjustments to conform to actual production shall not exceed the tolerances specified for the job mix formula limits. Regardless of such tolerances, the adjusted job mix formula shall be within the mixture specification master gradation bands. Should a redesign of the mixture become necessary, new job mix formula asphalt content may only be reduced if the production voids in mineral aggregate meets or exceeds the minimum voids in mineral aggregate design requirement for the mixture being produced. The request for JMF change must be requested in writing. See Figure 1 - Example - Request for JMF Change Form. The request for JMF change form should have a list of items as per Figure 1. The purpose of the JMF change form is to provide verification and records of the new JMF requests. The JMF change form is a permanent project record and shall be maintained as part of the project records. CMM Job Mix Formula (JMF) Changes A JMF binder content decrease of at least 0.1% from the original JMF target will require a new mix design. Changing the contract specified PG requires engineer approval and compliance with CMM Addition of an additive to a JMF, except approved compaction aids, will require an approved JMF change. Changes of an additive identified on a JMF, or the dosing rate, will require an approved JMF change. Elimination or addition of any aggregate component requires a new mix design. Changes to the design aggregate component blend percentages are limited to 20% in combination. (See number 3). No JMF change requests are to occur prior to completion of three individual production tests. Data from prior production testing do not have to be from state projects, but must be sampled and tested by HTCP certified personnel. Testing must occur in a WisDOT approved laboratory, following WisDOT approved methods. When making a Request for JMF Change, all laboratory results shall be submitted (electronically) to substantiate the use of materials from non-wisdot projects. The contractor will notify the engineer of the proposed change using the "Request for JMF Change" form (Figure 10). Comments must include the sample test number indicating when the change is to become effective. Production adjustments and Requests for JMF Change submittals may not cause any target value to violate design requirements. Production tolerances may exceed those targets. The requested change may become effective up to four individual tests before the request was formally made. Documentation (electronic) that the contractor and engineer had discussed a possible JMF Change must exist for the change to occur at a point prior to the test number on the formal request. Further changes will not be allowed until six additional individual test points, according to the normal sampling frequency, for the affected mix property have been documented. Each JMF sieve will be considered as an individual mix property. Control chart(s) for the affected property(ies) will accompany the "Request for JMF Change" (Figure 1). An example JMF mix design worksheet is shown in Figure 2. WisDOT Policy JMF Changes for Asphaltic Mixtures

88 TOPIC E: Quality Control Organizational Plan Page E-7

89 TOPIC E: Quality Control Organizational Plan Page E-8 Quality Management Process Flow A quality management process flow has been developed to guide the appropriate sequence of events for troubleshooting a QC/QV project. In summary, the quality management process guide consists of two main branches, QC and QV team. The first step is to conduct a preconstruction meeting to review all quality management specifications before project start-up. For example, WisDOT standard specification states The contractor shall furnish and maintain a laboratory at the plant site. The laboratory shall be furnished with the necessary equipment and supplies for performing contractor quality control testing. During the preconstruction meeting, topics of discussion should be the desired location, utility hook-ups, and date(s) laboratory will be set up prior to project start-up. The main purpose of the quality management process flow is to establish open communication channels and ensure each team, QC and QV, understands its specific responsibilities and occupational duties. Asphaltic Mixture Sampling Plan As an HMA-IPC Technician, you have experienced: Random sampling of asphaltic mixtures Sampling from stockpiles and off conveyor belts Sampling asphalt mixture from a truck box Reduction of asphaltic mixture samples to test size

90 TOPIC E: Quality Control Organizational Plan Page E-9 Random Sampling Exercises 1. Who is responsible for making a JMF adjustment in the field? 2. The production for one day will be 2700T. How many samples are required? 3. Determine the tonnage sampling plan for 2700 tons. Tonnage Increment x Sample No. Range Random # Random # +Prev. Increm. Final Sample Ton

91 TOPIC F: CMM/ Standard Specifications Note: Check the CMM and standard specifications link to verify the latest version

92 Construction and Materials Manual Chapter 8 Materials Testing, Sampling, Acceptance Section 65 Asphaltic Binder Materials Wisconsin Department of Transportation Materials sampling and testing methods and documentation procedures prescribed in chapter 8 of the CMM are mobilized into the contract per standard spec and standard spec Asphalt material sampling and testing methods as prescribed in CMM 8.65 are mobilized into the contract per standard spec and standard spec General Each asphalt binder provided to the project must be tested. A change in supplier or asphalt grade or designation constitutes a new binder. The number of samples to be taken and the sampling method used must be in accordance with the current version of the Combined State Binder Group Certification Method of Acceptance for asphalt binders and is summarized here within Sampling Asphaltic Materials The method for sampling asphalt PG binders must be in accordance with the current version of the Combined State Binder Group Certification Method of Acceptance for Asphalt Binders. For all other types of asphaltic materials, see standard spec 455. Regional personnel will be responsible for observing the sampling procedure, filling out and attaching sample tags, and shipping of the samples procured at the job site. They should also make sure the following points are given appropriate attention: 1. Sample per CMM Solvent or solvent-saturated cloth should not be used to clean the inside of the containers. The insertion of a solvent-saturated glove into the container during handling is an undesirable practice that could contaminate the sample. 3. The sample should always be taken in the containers to be sent to the laboratory. Do not transfer the sample from one container to another. 4. Before sample is taken from the sampling valve, a minimum of 4 L (1 gal) shall be drawn through the sample valve and discarded. 5. The sample containers should be relatively full. A good guide would be to fill the container to within one-inch of the top. In a few instances, insufficient material has been submitted for the required testing. After the container has been properly closed, do not use any cleaning solvent in the area of the closure. 6. After the asphaltic material has been properly sampled and labeled, ship to the laboratory the same day, if feasible. Shipments that take an excessive amount of time to arrive at the laboratory and those inappropriately sampled may cause test results that deviate from the contract requirements. Samples should be shipped with a sample tag, DT1352 (a blank form is available for use at this link.) See Figure 1 for an example on what is required to be filled out on the sample tag: Figure 1 Asphalt Binder Sample Tag NOT FOR CONTRACT ADMINISTRATION December 2016 Page 1

93 CMM 8-65 Asphalt Certification Method of Acceptance for Asphalt Binders Acceptance of asphalt binder by the Certification Method provides for acceptance of these materials for use on WisDOT projects upon the producer's or supplier's certification that the product as furnished to the contractor (or purchasing agency) complies with the pertinent specification and/or contract requirements. A list of certified suppliers can be found in the Combined State Binder Group Certification Method of Acceptance for Asphalt Binders document or on the department s approved product list at: For samples tested by the department with non-complying results, the engineer should ensure that the procedure listed in the Certification Method has been followed (ex: AASHTO T-164). NOT FOR CONTRACT ADMINISTRATION December 2016 Page 2

94 Construction and Materials Manual Chapter 8 Materials Testing, Sampling, Acceptance Section 66 Asphalt Mixture Design Wisconsin Department of Transportation Materials sampling and testing methods and documentation procedures prescribed in chapter 8 of the CMM are mobilized into the contract per standard spec and standard spec Asphalt material sampling and testing methods as prescribed in CMM 8.66 are mobilized into the contract per standard spec and standard spec 460. Several revisions were made, see red text ASPHALTIC MIXTURE DESIGN Provide an Asphaltic Mixture Design Job Mix Formula (JMF) report representing the materials intended for use along with their proportions for producing the final product. These procedures infer laboratory mixed and compacted specimens unless designated otherwise. Accountability for JMF Mix Design Reports is to be with Highway Technician Certification Program (HTCP) certified personnel and comply with the materials and mix design requirements of standard spec 460. If a contractor uses a consulting laboratory to supply a mix design, the Contractor must authorize in writing that the consultant acts as the contractor s agent during the mix design approval process. During the mix design submittal process, WisDOT will only accept two (2) passing designs per each nominal maximum aggregate size or one (1) mix design per combined bid item (whichever is greater), per project. During construction, any approved mix design matching the pay item may be used. When a mix design is to be submitted using Atwood s System a current WisDOT project is required. The following default WisDOT project number shall be used on the 249 submittal form when a current WisDOT project number is not available at time of design. An example would be a non-dot project requiring a DOT approved mix design. Any mix design approaching expiration, can be renewed with a one point verification and will retain its original 250 number when renewed on the approved list. Any mix design that had been issued a 250 number not using the 249 form may contact the Bureau of Technical Services (BTS) for instruction on how to obtain a 250 number in the current calendar year Acronyms and Definitions Interpret materials related acronyms and definitions in accordance with standard spec Laboratory Standard Method of Asphaltic Mix Design (previously called WisDOT Test Method 1559) Description This method is used to determine the optimum asphalt binder content for virgin asphaltic mixtures and asphaltic mixtures containing recycled asphaltic materials (RAM). This method also defines the submittal requirements pertaining to mix design reports and materials, as well as any field changes affecting mix design reports General Required test procedures for aggregate and hot mix asphalt (HMA) are shown below in Table 1 and Table 2. NOT FOR CONTRACT ADMINISTRATION May 2017 Page 1

95 CMM 8-66 Asphalt Table 1 Required Aggregate Test Procedures AGGREGATE TEST TEST PROCEDURE Materials Finer than No. 200 (0.75mm) AASHTO T 11 Sieve Analysis of Aggregates AASHTO T 27 Mechanical Analysis of Extracted Aggregate AASHTO T 30 Sieve Analysis of Mineral Filler AASHTO T 37 Liquid Limit of Soils (from source aggregate quality report #225 or #162) AASHTO T 89 Plastic Limit of Soils (from source aggregate quality report #225 or #162) AASHTO T 90 Los Angeles Abrasion of Coarse Aggregate (from #225 report) AASHTO T 96 Specific Gravity and Absorption of Fine Aggregate AASHTO T 84 Specific Gravity and Absorption of Coarse Aggregate AASHTO T 85 Flat and Elongated Particles in Coarse Aggregates ASTM D4791 Soundness of Aggregate (from #225 report) AASHTO T 104 Freeze-Thaw (from #225 report) AASHTO T 103 Fractured Faces (CAA) ASTM D5821 Uncompacted Voids Content of Fine Aggregates (FAA) AASHTO T 304 Sand Equivalency (Plastic Fines) AASHTO T 176 Note: The majority of test result parameters are referenced in Table in standard spec or Table in standard spec Table 2 Required HMA Test Procedures HMA TEST Practice for Superpave Volumetric Design for HMA Specification for Superpave Volumetric Mix Design Standard Practice for Mixture Conditioning HMA TEST PROCEDURE AASHTO R35 AASHTO M323 AASHTO R30 Standard Method for Preparing and Determining the Density of HMA AASHTO T 312 Specimens by Means of the SHRP Gyratory Compactor Bulk Specific Gravity of Compacted Bituminous Mixtures AASHTO 166 Using Saturated Surface-Dry Specimens Maximum Specific Gravity of Bituminous Paving Mixtures AASHTO 209 % Air Voids in Compacted Dense and Open Bituminous Paving Mixtures AASHTO 269 Resistance of Compacted Bituminous Mixture to Moisture Determination of Draindown for Uncompacted Asphalt Mixtures ASTM D4867 AASHTO T305 WisDOT Standard Specifications for Asphaltic Concrete Pavement standard spec 460 NOT FOR CONTRACT ADMINISTRATION Quantitative Extraction of Asphalt Binder from Hot Mix Asphalt (HMA)* Asphalt Content by Ignition Oven* Note: * these are not required as part of the mix design process AASHTO T164 AASHTO T Summary of the Practice 1. Select aggregate components and the asphalt binder to be used, and determine the required properties defining those materials. 2. Design an aggregate structure (or multiple trial aggregate structures). Determine aggregate component blend percentages. 3. Determine trial asphalt binder contents (estimated by experience or by calculation based on aggregate properties of trial blends). May 2017 Page 2

96 CMM 8-66 Asphalt - Compact gyratory specimens using a minimum of 3 times, preferably 4, asphalt binder contents (0.5% increments) and covering a range to include the estimated optimum design binder content. Use Ndes for compaction effort. - All new mix design need at least one point that is a minimum of 0.5% below 3.0% Air Voids ( 2.5% Va) and one point that is at least 0.5% above 4.0% Air Voids ( 4.5% Va) - Compare trial binder content results. Select an optimum design binder content (by either graphing or interpolating the trial data results) meeting requirements as stated in standard spec Evaluate additional properties at the selected optimum design binder content. - Moisture Susceptibility (using ASTM D4867). - Validate compliance of %G mm at N max and N ini by compacting 2 specimens at the design binder content to Nmax gyrations. - For SMA designs, AASHTO T305 must be followed and testing conducted at two temperatures. The two temperatures should be the anticipated production temperature and +15 C about the anticipated production temperature. Mix must be prepared at optimum AC%. Report the average percent Draindown (average percent of the mixture that drained) at each of the test temperatures. - Draindown value at anticipated production temperature and at 15 C above anticipated production temperature, average of two (2) values at each temperature is required. 5. Complete a mix design report identifying materials used and summarizing volumetric properties in meeting required specifications in CMM Submit the mix design report, and representative materials when requested or required, to the department for review per CMM Additional guidance for materials selection and component composition involved in the mix design process can be referenced in, but not limited to, the following: Superpave Mix Design Manual SP-2 (Asphalt Institute) Mix Design Methods for Asphalt Concrete MS-2 (Asphalt Institute) NCHRP 9-33 (A Mix Design Manual for Hot Mix Asphalt) NCHRP Report 673 (A Manual for Design of Hot Mix Asphalt with Commentary) Materials and Test Procedures: Additional Guidance Aggregates Refer also to CMM 8-60 and standard spec Test the aggregate source material for quality properties (LA wear, soundness, freeze-thaw, etc.) in accordance with the current department policy and required frequency. Count the current construction season as one year of aggregate quality eligibility. The mix designer, using the previously listed test methods determines the aggregate properties with the following exceptions or comments: - Fine aggregate angularity (FAA) is determined using Method A (AASHTO T 304) on each individual component with more than 10% passing #8 sieve (2.36mm) and on the current JMF blend. - A specific gravity must be completed on each P-#8 component following AASHTO T84. The extracted aggregate from RAM shall be obtained through the extraction process by either of the following: - Ignition oven - Chemical extraction - Flat and elongated particles are determined using particles retained on the #4 sieve (4.75mm) and larger. The determination of the F&E percentage is based on weight; however, the sample size is intended to be by count (200 pieces, minimum). NOT FOR CONTRACT ADMINISTRATION Asphaltic Binder Material Select an asphalt binder meeting the contract requirements and having been defined or graded according to AASHTO M320. (refer to CMM 8-65) The asphalt binder source and grade indicated on the JMF Mix Design report must represent the material used during the mix design process in determining the optimum asphalt content as well as during production. If recycled asphaltic materials are part of the mix design additionally refer to standard spec May 2017 Page 3

97 CMM 8-66 Asphalt It is permissible to increase binder designation grade from that submitted and approved at the time of the mix design submittal to the time of production. However, a decrease in binder designation requires a one point verification test be submitted. If the PG grade changes from original design, a one point verification test is required. All one point verification tests are to be run at %AC corresponding to 4.0% air voids at Ndes number of gyrations. If the following criteria are met, no additional testing is needed to increase the binder designation from the new base binder. However if any of the following criteria are not met by a one point verification test, a complete design submittal is required: Property JMF Criteria TSR* > 77%** %Gmm at Nini <88.5 (for HT mixes) %Gmm at Nmax < 97.5 * Compacted using AC corresponding to 4.0% air Ndes at 7.0% (+/- 1.0%) air voids, using current JMF blend, with all current approved JMF changes. - If the resultant verification check (one-point) indicates a need to adjust the mix design targets or component combinations to meet specifications, then additional testing and separate design submittal is required. Changes in the asphalt binder source during production must be documented showing the new supplier is on the current WisDOT's approved products (APL) Preparation of Mixtures Combine the aggregates and asphaltic binder noting the following exceptions: - The requirement for using trial aggregate blends as prescribed in AASHTO R35 is optional. - Compaction effort gyrations are set by WisDOT standard specs and may deviate from AASHTO R35. Additionally refer to standard spec Compaction of Specimens Produce the required compacted specimens (minimum of 2 specimens for each asphalt binder content) using AASHTO T 312 and AASHTO R30. For aggregate JMF blends with moisture absorption greater than or equal to 2.0% a 4-hour cure time is to be used and indicated on the JMF mix design report. Report the actual absorption value on the report and additionally state the cure time within the report or comment section Determination of the specific gravity of SGC compacted asphaltic (G mb ) Determine specimen Bulk Specific Gravity (G mb ), using AASHTO T 166, Method A for dense-graded mixes. For open-graded mixes such as SMA, determine Bulk Specific Gravity using AASHTO T 331. Report G mb value to three decimal places (0.001) Determination of the mixture maximum specific gravity (G mm ) Determine Maximum Specific Gravity, (G mm ), using AASHTO T 209. For aggregate JMF blends with moisture absorption greater than or equal to 2.0%, additionally use the supplemental procedure for mixtures containing porous aggregates not completely coated (dry back procedure). This data is to be listed on the JMF mix design report. A minimum of two tests must be run, one each at two different asphalt trial binder contents. Calculate the G se for each Gmm test run (to three decimal places, 0.001) and average the results. Use this calculated average Gse to determine all G mm values for the trial data. Report any G mm value to three decimal places (0.001). NOT FOR CONTRACT ADMINISTRATION Report General The mix designer/laboratory creates a summary report to be submitted electronically into Atwood s Systems using the 249 form for review, along with an electronic copy (pdf of 249 form and mix design report) to BTS and the regional office. This summary must include trial data used to determine the design optimum binder content Report Items The following is a breakdown of the minimal information needed to be listed on the mix design report. An example May 2017 Page 4

98 CMM 8-66 Asphalt report can be found at the end of this section. Summary of Aggregate Source/Component and RAM Data: - Source name (as noted on 225 report), pit or quarry designation (P or Q), and 225 number, for each component, using the following format (225-xxxx-xxxx). - Component Gradations: gradations for each aggregate and the final blend must be shown as the % passing (the nearest 0.1) for the1 ½ (37.5mm), 1 (25.0mm), ¾ (19.0mm), ½ (12.5mm), 3/8 (9.5mm), #4(4.75mm), #8(2.36mm), #16(1.18mm), #30(0.60mm), #50(0.30mm), #100(0.150mm), and #200(0.075mm) sieves. - The percent of each aggregate and/or RAM component as compared to the total aggregate. - LA Wear loss, % (include department test number or listed values). - Soundness loss, % (include department test number or listed values). - Freeze-thaw, % (include department test number or listed values, refer standard spec ). - Aggregate Bulk specific gravity (G sb ). - For mixtures containing RAM extracted gradation data, G sb and percent extracted asphalt content is required. - Flat and elongated (Method B), %. - Coarse fracture/crush count (1-face and 2-face), %. - Fine aggregate angularity (Method A) for fine aggregate only. i.e.: Sands (Natural, Manufactured) and P#8 of RAM components. - Moisture absorption %. Aggregate Blend Data: - Flat and elongated (Method B), %. - Coarse fracture/crush count, %. - Sand equivalency. - Fine aggregate angularity. - Moisture absorption %. - Bulk specific gravity (G sb ). - Effective specific gravity (G se ). Asphaltic Binder: - Binder source (supplier). - Binder performance grade and designation level (S, H, V, or E). - Binder specific 77 / 77F (25 / 25C). - Laboratory Mixing- and Compaction - Temperatures (based on AASHTO T 312) for laboratory produced mixture evaluation, see CMM (2). - Type of Additive - Amount of Additive Mixture Properties (using trial asphalt binder contents) - Binder content, % (P b ). NOT FOR CONTRACT ADMINISTRATION - Air Voids, % (V a ). - Maximum specific gravity (G mm ). - Bulk specific gravity of the compacted mixture (G mb ). - VMA (voids of the mineral aggregate), %. - VFB (voids filled with binder), %. Mixture Properties (design optimum asphalt binder content): - Binder content, % (P b );. - Maximum specific gravity (G mm ). May 2017 Page 5

99 CMM 8-66 Asphalt - Bulk specific gravity (G mb ). - Air voids, % (V a ). - VMA (voids of the mineral aggregate), %. - VFB (voids filled with binder), %. - DP (dust/binder proportion), % (using effective binder content, P be, for calculation). - Gyratory compaction effort (for Nini, Ndes and Nmax). - %Gmm (for N ini, N des and N max ). - TSR (tensile strength ratio), %. - TSR Compaction Effort (N = x ). - Gmm Dryback Correction Factor, % (if applicable). Mixture Properties (3.0% Air-Void Regression asphalt binder content): - Binder content, % (P b ); - Maximum specific gravity (G mm ). - Bulk specific gravity (G mb ). - Air voids, % (V a ). - VMA (voids of the mineral aggregate), %. - VFB (voids filled with binder), %. For Recycled Asphaltic Pavement Mixtures also list: - Added binder content, %. - Total binder content, %. - Extracted asphalt binder % (of recycled components) - Percent Binder Replacement (Pbr) Miscellaneous: - Name of WisDOT - HTCP Certified HMA technician (at level designated for mix design) identifying responsibility for mix design data. - Name of design laboratory facility, its address and phone number (contact location). - Design date (representing completion of the mix design work). - Design ID (unique number or name). - Traffic level classification (e.g. LT, MT, HT). - Asphalt mixture gradation (NMAS) (e.g., Gradation 1, 2, 3, 4, 5 or 6 representing 37.5mm to 4.75mm, respectively). - Report draindown results (at two temperatures) Report Submittal and Department Review General Mix design summary reports, and either individual or batches of blended aggregates (if required or requested), are to be submitted to WisDOT - Bureau of Technical Services (BTS) prior to paving, using one of the following two methods: Comparison Level or Express Level. Each mix designer will be subject to a minimum of one comparison level submittal per year. In addition mixes meeting the following criteria should have material submitted to BTS: Design values for VMA (+0.5%), FAA (+1.0%), or TSR are within +5% of the lower limit requirements in standard spec , tables & 2, may be selected for comparison submittal. The 10 day limit for comparison submittal does not apply. NOT FOR CONTRACT ADMINISTRATION In addition to the above requirements for comparison mix design submittal, BTS requires any BTS-selected mixes be submitted for performance-based testing: Note: If a mix design is selected for both comparison and performance-based testing, only one batch of gram specimens and 3-quarts of asphalt binder are required to be submitted to BTS, this does not preclude TSR specimens (8), which must still be prepared and submitted. May 2017 Page 6

100 CMM 8-66 Asphalt The specific mix subject to this requirements will be determined by BTS and communicated to each mix designer. Designation of a design laboratory, or a certified mix designer to a specific submittal level is determined by the BTS. BTS will authorize and direct movement between submittal levels. Submittals received after 4pm (Mon-Fri) will be acknowledged as arriving the following work day. Each design must be submitted using WisDOT form 249, WisDOT Mix Design Standard Data Detail through WisDOT Material Reporting System (MRS).Contractor to provide electronic notification to BTS and the regional HMA Specialist when form 249 is submitted. A blank form 249 is available at: Only one mix design per notification will be accepted. At BTS s discretion, any or all of the following testing may be performed: Aggregates: - Test the aggregate for compliance to standard spec , Table 460-2: - Flat and elongated (Method B), % - Coarse fracture/crush count (1-face and 2-face), % - Sand equivalency - *Fine aggregate angularity (Method A) - Moisture absorption % - *Bulk specific gravity (Gsb) - Note:* Gmb and Gmm need to meet tolerances in Table 3 of CMM 8-66, compared to results provided on original Mix Design submittal. HMA: Test the HMA for compliance to standard spec , Tables and Note: *Gmb and Gmm need to meet tolerances in Table 3 of CMM 8-66, compared to results provided on original Mix Design submittal. Table 3 Allowable Differences between Contractor and BTS Comparison Test Results Test Allowable Difference Mixture bulk specific gravity (Gmb) +/ Mixture maximum specific gravity (Gmm) +/ Fine Aggregate Angularity (Method A), uncompact voids (%) - 1 Aggregate Individual Bulk Specific Gravity (+No. 4 [+4.75mm]) (Dry) +/ Aggregate Individual Bulk Specific Gravity (-No. 4 [-4.75mm]) (Dry) +/ Note: Individual component aggregates may be tested; where upon adequate material shall be required for testing, communication between BTS and the mix designer shall take place beforehand before requesting materials. NOT FOR CONTRACT ADMINISTRATION If BTS s test results are less than the values in Table for minimum TSR values, the mix may need to be redesigned and tested, also all future submittals using this source may require the submission of TSR samples for verification/acceptance testing until BTS is satisfied with the source. Communication with BTS is required and all testing is at the discretion of BTS Comparison Level Submittals This process requires submittal of the mix design summary report and blended aggregates representing the mix design Job Mix Formula (JMF). Materials are to be submitted to the department a minimum of 10 working days prior to paving. - Include 4 (four) 6800g (15 lb) batches of the blended aggregate, representing the mix design JMF, (inclusive of any components containing Recycled Asphaltic Materials) and a minimum of three (3) quart cans of design PG binder. - Or BTS may request individual aggregate/ram samples for each component and a minimum of three (3) quart May 2017 Page 7

101 CMM 8-66 Asphalt cans of the design PG binder in place of the composite aggregate samples. If TSR s are requested, the contractor will supply 8 (eight) - compacted specimens to BTS. Compact specimens to 7.0 +/- 1.0%, air voids. The following conditions shall indicate a need to follow this submittal procedure (communication with BTS is required): 1. Any design laboratory or certified asphalt mix designer submitting designs to the BTS for the first time (regardless of previous history for either). 2. Any design laboratory or certified asphalt mix designer having lacked submittals for a period of three consecutive construction seasons. 3. Any design laboratory or mix designer abusing the express submittal privilege (ex: multiple instances of incorrect or non-compliant data/information needing correction or formal amendment). Note: This condition will be identified and communicated when trending and then defined by notification from the BTS. The Superpave Mix Design may be refused, or the review may be stopped, if any of the following situations occur (but not limited to): - Evaluation of Superpave Mix Design results indicates a failing design. - Incorrect or insufficient material is submitted. - Incomplete documentation. - Aggregate(s) do not meet physical requirements specified per Table The Contractor/Consultant requested combined gradation does not meet Table Aggregate Gradation Master Range. - No BTS office notification (of comparison level samples being sent to BTS). - Invalid Aggregate Quality Number. - Contractor/Consultant suspends interest in submitted material. - Other unforeseen situations as deemed by BTS. Subject to BTS workload and after the contractor/consultant efforts are made to resolve all discrepancies in the submittal, the ten (10) day review procedure will resume. Transition from comparison level submittal requirements to express submittals will be by notification from BTS. Results of the comparison review shall be compared. When tolerances are exceeded in Table 3 or if the results are less than the requirements in standard spec , Tables & 2, a new mix design may need to be completed and submitted by the Contractor/Consultant Express Submittal Design laboratories or certified designers may use this submittal procedure with authorization from BTS. The design laboratory must submit the mix design summary report (electronically) to the department for review and provide a copy to the department s regional office a minimum of 4 working days prior to start of paving. 1. The department will review the mix design summary report and acknowledge specification compliance by the following 4th work day after submittal. In the event that the submitted design does not meet specifications, or the individual contract requirements, the department will notify the mix designer and may elect to delay release of the review (potentially impacting paving); until such time that the specifications are met. HTCP Certified mix designers requesting mix design comparison testing should follow the requirements for Comparison Level submittals and alert the Bureau of Technical Services Truax Center Laboratory of the request to have properties checked. Use of this submittal procedure, while authorized for Express Level, does not negate further use of Express Level submittals. NOT FOR CONTRACT ADMINISTRATION Mixture Design Life All HMA mix designs shall have a life of 3-years from the date of the initial assigned WisDOT 250 number. Count the current construction season as year one of mix design life eligibility. For any mix design to surpass the 3-year life, a one-point verification using lab or field produced materials is required as described in One-point verifications are to be conducted on the current JMF blend (including all current approved JMF changes) and %AC corresponding to 4.0% air voids using Ndes gyrations. Results must be submitted electronically to BTS - Truax for review along with the current mix design including any current approved JMF May 2017 Page 8

102 CMM 8-66 Asphalt changes. Individual specific gravities must not vary more than the allowable differences in table 4. BTS will review the submitted data with-in 4 (four) working days and if compliant the mix shall then be placed on the approved HMA Mix Design List for another 3-year cycle. BTS will review the results to verify they are not less than the requirements listed in Tables & 2 of the Standard Specifications. The percent binder replacement (Pbr) in section shall also be verified and reported to show results are within allowable tolerances. Note: The tolerances in Table 4 shall be used to evaluate the one-point verification test results. Previously approved mix designs not meeting the requirements of the Air Void Regression specification (i.e., having a point 3.0% Air Voids), require an additional point be run at the next lower 0.5% AC increment. In this instance, mixes are to be entered into MRS using the 249 form and will be assigned a new 250#. The previously assigned 250# number associated with the mix (prior to conducting the next lower 0.5% AC increment) will become inactive. Table 4 Allowable Differences for One-Point Verification Check Test Results HMA Allowable Difference Air Voids (Va) % +/- 0.5 Aggregates Allowable Difference Aggregate Individual Bulk Specific Gravity (+No. 4 [+4.75mm]) (Dry) +/ Aggregate Individual Bulk Specific Gravity (-No. 4 [-4.75mm]) (Dry) +/ A mix design shall carry over for subsequent construction seasons, with-in the 3-year design life, when all of the following are met: 1. Department specification changes have occurred, and the mix design still meets those specifications for any current contract. 2. Aggregate quality data is current per standard spec See department 162 and 225 reports for approved aggregate sources on WisDOT's approved products list (APL). 3. Design aggregate component blend percentages will not be changed by more than 20% in any combination at any single point during production. a) Note that any single component blend adjustment will result in a need to adjust additional components to balance the blend (e.g.: any component adjusted by 10% will also require an additional other 10% change between the remaining components, resulting in the maximum 20% referenced change). However, component blend changes are not accumulative so component blend changes back towards the original JMF will not be considered as exceeding the 20% maximum. The following example illustrates changes to proportions and how to assess blend changes: 1. For example if the original proportions for the aggregates are: Agg1 = 25%, Agg2 = 25%, Agg3 = 45%, Agg4 = 5%.Then the initial component blend first changes by adjusting Agg1 to 35% and Agg2 to 15% resulting in a 20% change from the JMF. Then a second change had Agg1 moved back towards the original JMF to 30% and changed Agg2 to 20% resulting in a 10% net change from the original JMF. The second change does not get added to the first change of 20%. Each change is independently assessed against the original JMF, not added to other previous changes. b) Blend changes indicating an excess of the maximum 20% away from the original JMF will not be considered the same mix design within the same season or any subsequent season. Continued use will require a new mix design or approval of the project engineer (documenting the reason). NOT FOR CONTRACT ADMINISTRATION Any need for elimination or addition of new aggregate (inclusive of RAM) components will require a new mix design. Additives including a change in the dosage rates may require additional testing to insure compliance. Recognizing all current design JMF target changes with associated QMP data from the end of the previous construction season shall be required and must be noted as such prior to initial paving. Current list of Approved Asphalt Mix Designs: Amended JMF Reports and JMF Report Reviews Previously submitted mix designs needing to be edited or updated will be re-submitted along with an explanation for the nature of the change (and any supporting data). Examples of these instances could be: 1. Typographical Errors May 2017 Page 9

103 CMM 8-66 Asphalt 2. Addition of PG binders in order to comply with CMM Mix Design Signatures (HTCP Accountability) Non Traditional or Non-Standard Mixture Design Reports Warm Mixed Asphalt (WMA): Laboratory work should be completed at additive supplier recommended mixing and compaction temperatures. These temperature ranges are to be listed on the JMF report and the mix design submittal 249. For mix designs involving specialty products, components, or needing to meet a local special provision, identify in the comment section of the report or within the submittal correspondence. NOT FOR CONTRACT ADMINISTRATION May 2017 Page 10

104 Section 450 General Requirements for Asphaltic Pavements Description (1) This section describes requirements common to plant mixed asphaltic bases and pavements. Exceptions and additional requirements are specified in 455 through Materials Acronyms and Definitions (1) Interpret materials related acronyms used in sections 450 through 499 as follows: FRAP Fractioned reclaimed asphaltic pavement HMA Hot mix asphalt JMF Job mix formula PG Performance graded RAP Reclaimed asphaltic pavement RAS Recycled asphalt shingles SMA Stone matrix asphalt VMA Voids in mineral aggregate WMA Warm mix asphalt (2) Interpret materials related definitions used in sections 450 through 499 as follows: Additive A material blended with asphaltic binder or aggregate to enhance the characteristics of the final HMA blend, but that does not alter the binder performance grade. Asphaltic binder The predominant asphalt cement in HMA. Filler Mineral fillers, used primarily to fill voids between aggregate particles to meet gradation requirements. Fractionated reclaimed asphaltic pavement Reclaimed asphalt pavement processed by screening and separating by maximum and minimum particle size, asphalt content, asphalt performance grade, and aggregate characteristics. Leveling layer A thin HMA layer placed to eliminate irregularities in the profile or thickness of underlying pavement layers. Lower layer An asphaltic pavement layer below the upper layer in the completed pavement structure. There may be multiple lower layers. Modifier A material blended with the asphaltic binder to enhance its characteristics by modifying the performance grade of the binder. Reclaimed asphaltic pavement Material resulting from cold milling or crushing existing asphaltic pavement. Recycled asphalt shingles Waste material from a shingle manufacturing facility, either new or used material salvaged from residential roofing operations, or any combination of these materials ground to ensure that 100 percent will pass a 3/8 sieve and processed to remove deleterious material. Upper layer The top asphaltic pavement layer in direct contact with traffic in the completed pavement structure. There is only one upper layer. Warm mix asphalt Asphaltic mixture containing a warm mix additive or using a warm mix process that reduces the mixing and compaction temperatures typically required for that application. Wedging A tapered layer of asphaltic pavement used to build up an existing surface. Wedging layers may be thicker or thinner than standard pavement layers Aggregate Sampling and Testing (1) The department and the contractor will sample and test according to the following methods, except as revised with the engineer's approval: Sampling aggregates... AASHTO T2 Material finer than No. 200 sieve... AASHTO T11 Sieve analysis of aggregates... AASHTO T27 Mechanical analysis of extracted aggregate... AASHTO T30 Sieve analysis of mineral filler... AASHTO T37 Los Angeles abrasion of coarse aggregate... AASHTO T96 Freeze-thaw soundness of coarse aggregate... AASHTO T103 NOT FOR CONTRACT ADMINISTRATION Effective with the December 2017 Letting Standard Specifications

105 Sodium sulfate soundness of aggregates (R-4, 5 cycles)... AASHTO T104 Extraction of bitumen... AASHTO T Construction Equipment Asphalt Plants Plant Scales (1) Provide beam, springless, dial, or digital scales on weigh boxes and silos. Use scales of a standard make and design accurate to within 0.5 percent of the maximum required load. For each plant, provide at least ten standard 50 pound weights accurate to within 0.1 percent. For each scale, provide a suitable cradle or platform for applying test loads. (2) If using beam scales for aggregate, provide a separate beam for each size of aggregate. Also provide a device that warns when the applied load is within 200 pounds of the required load. (3) If using beam scales for asphaltic materials, provide a tare beam and a full capacity beam with a minimum graduation no greater than 2 pounds. Also provide a device that warns when the applied load is within 20 pounds of the required load. (4) If using dial scales, provide a standard make springless scale designed, constructed, and installed to be vibration free. Ensure that all dials are plainly visible to the operator at all times. Equip with adjustable pointers for marking the weight of each material batched. (5) If using digital scales, conform to National Bureau of Standards Handbook Automatic Batching (1) On contracts with 10,000 tons or more, provide automated batch plants. Ensure that the plants' control system can coordinate mixture proportioning, timing, and discharge by the operation of a single control. Also provide an automatic batch weighing, cycling, and monitoring system. (2) On contracts with less than 10,000 tons, if the contractor elects to use batch plant automatic systems, conform to the requirements here under The contractor need not use automatic recordation. If the contractor elects to use automatic recordation, conform to for truck loads, or for batch weights. (3) Ensure that the system accurately proportions mixture components by weight or volume in the proper order and controls the mixing cycle sequence and timing. Provide interlocks that ensure that the scale is at zero before a batch can start and that the batch is mixed completely before discharge. Do not start subsequent batches before completely discharging the previous batch. Also provide interlocks that ensure that all batch materials are in the mixer before the batch can discharge. Ensure that unauthorized personnel cannot alter mix designs and that equipment emits an audible signal if discharging a batch with out-of-tolerance component weights. Ensure that this signal is loud enough to hear throughout the plant area under normal operating conditions. (4) Provide adjustable timing devices to control individual component batching and mixing operations. Provide auxiliary interlock cutoff circuits necessary to stop automatic cycling whenever an weighing error exceeding a specified tolerance occurs or when another part of the control system malfunctions. (5) Ensure that the batching system automatic control can stop the cycle in the underweight check position and the overweight check position for each material to check tolerance limits. (6) Ensure that the scale system is equipped with a device that applies pressure to a scale lever to simulate batching operations for tolerance checks. (7) Consistently deliver materials within the full range of batch sizes within the following tolerances: MATERIAL PERCENT OF TOTAL MATERIAL BATCH WEIGHT Coarse aggregate Fine aggregate Aggregate for use with salvaged or reclaimed pavement materials Mineral filler Salvaged or reclaimed asphaltic pavement material Asphaltic material Zero return for aggregate Zero return for salvaged or reclaimed material Zero return for asphaltic material NOT FOR CONTRACT ADMINISTRATION Effective with the December 2017 Letting Standard Specifications

106 (8) Unless providing separate tolerance controls for batching mineral filler, reduce aggregate tolerances to +/- 0.5 percent for aggregates delivered before the filler. (9) Ensure that the total weight of the batch does not vary by more than +/- 2.0 percent of the designated batch weight. (10) Ensure that the electrical circuits for the above delivery tolerances of each cutoff interlock are capable of providing the total span for the full allowable tolerance for maximum batch size. Provide tolerance controls automatically or manually adjustable to provide spans suitable for less than full-size batches. Ensure that the automatic controls and interlock cutoff circuits are consistently coordinated with the batching scale or meter within an accuracy of 0.2 percent of the scale or meter nominal capacity [1] throughout the full range of the batch sizes. [1] Nominal capacity of a scale is defined as the maximum quantity which the scale or meter can measure. (11) If the automatic control or monitoring systems break down, the contractor may operate the plant manually for up to 2 working days Recording Batch Weights (1) On contracts involving 10,000 tons or more of asphaltic mixtures, unless the contractor elects to record truck loads as provided in , produce an automatic digital record for each batch indicating the proportions of each aggregate component, mineral filler, and asphaltic material. (2) Provide a digital recorder that can print multiple copies of mixture reports that give the total weight of asphaltic mixture and asphaltic material both per load and per batch. Include weights of the individual aggregates and fillers. Reports need not provide tare weight and may use accumulative weights. Ensure that reported weights are accurate within +/- 1 kg/500 kg. Allow sufficient time for the scale to come to rest before printing each weight. (3) The contractor may use mixture storage silos with digital recorder equipped batch plants if the department determines the storage silo output is coordinated with the recorded batch weights. (4) If the recording system breaks down, the contractor may operate the plant without automatic recording for up to 2 working days Recording Truck Loads Revise to add more required load ticket information including cold weather paving information. This change was implemented in ASP 6 effective with the December 2016 letting. (1) If not using automatic batch recording, install a digital recorder as part of the platform truck or storage silo scales. Ensure that the recorder can produce a printed digital record of at least the gross or net weights of delivery trucks. Provide gross, tare, net weights, load count, and the cumulative tonnage; the date, time, ticket number, WisDOT project ID, and mix 250 number; and the mix type including the traffic, binder, and mix designation codes specified in Ensure that scales cannot be manually manipulated during the printing process. Provide an interlock to prevent printing until the scales come to rest. Size the scales and recorder to accurately weigh the heaviest loaded trucks or tractor-trailers hauling asphaltic mixture. Ensure that recorded weights are accurate to within 0.1 percent of the nominal capacity of the scale. (2) Ensure that tickets identify additives not included in the mix design submittal or cold weather paving plan. Indicate on the ticket if the mixture is placed under a cold weather paving plan Asphaltic Mixture Hauling Vehicles (1) Provide trucks for hauling asphaltic mixtures with tight, clean, and smooth boxes. The contractor may thinly coat boxes with a release agent chosen from the department's APL. Drain excess release agent after coating. Equip each box with a cover big enough to protect the mixture. Do not use trucks that show oil leaks of any magnitude Transfer Devices (1) Ensure that transfer devices have surge bin capacity adequate to pave continuously at a uniform speed. If maintaining uniform and continuous paving, the engineer may allow the contractor to omit the surge bin. Do not use devices that cause vibrations or other motion that adversely affect the finished ride Pavers (1) Ensure that the screed or strike-off assembly produces a finished surface of the required evenness and texture without tearing, shoving, or gouging the mixture. Use a screed adjustable for the required crown and cross-section of the finished pavement. (2) Ensure that pavers are equipped with an activated screed or strike-off assembly and use activation at all times during paving unless the engineer allows otherwise. Do not extend the screed with one or NOT FOR CONTRACT ADMINISTRATION Effective with the December 2017 Letting Standard Specifications

107 more static extensions totaling more than 12 inches at either screed end, except at the shoulder end for paving shoulders. (3) Provide pavers with department-approved automatics that control the elevation and slope of the screed. The department will not require automatic controls when paving entrances, approaches, side road connections, small irregular areas, or if the engineer determines using automatic controls is impracticable. Use both grade and slope controls whenever automatics are required, except the engineer may waive the longitudinal or grade control requirement for the final surface. Ensure that the operator can adjust or vary the slope throughout super elevated curves and transitions. Also ensure that the system allows the sensor to operate on either side of the paver. (4) If automatics break down, the contractor may pave under manual control only until the end of that working day Compaction Equipment (1) Ensure rollers are in good mechanical condition, capable of operating both forwards and backwards, and the operating mechanism allows for starting, stopping, or reversing direction in a smooth manner, without loosening or distorting the surface being rolled. (2) Equip rollers with a drum or tire lubricator. Do not lubricate with petroleum or tar products Constructing Asphaltic Mixtures General Preparation and Paving Operations (1) Do not place asphaltic mixture when the air temperature approximately 3 feet above grade, in shade, and away from artificial heat sources is less than 36 F for upper layers or 32 F for lower layers unless the engineer allows in writing. The contractor should place HMA pavement for projects in the northern asphalt zone between May 1 and October 15 inclusive and for projects in the southern asphalt zone between April 15 and November 1 inclusive. CMM 4-53 figure 2 defines asphalt zones. Notify the engineer at least one business day before paving. (2) Unless the contract specifies otherwise, conform to the following: - Keep the road open to all traffic during construction. - Prepare the existing foundation for treatment as specified in Incorporate loose roadbed aggregate as a part of preparing the foundation, in shoulder construction, or dispose of as the engineer approves. (3) Place asphaltic mixture only on a prepared, firm, and compacted base, foundation layer, or existing pavement substantially surface-dry and free of loose and foreign material. Do not place over frozen subgrade or base, or where the roadbed is unstable Cold Weather Paving General (1) Conform to these cold weather paving provisions for work performed under the following: - The 460 HMA Pavement bid items. - The 465 Asphaltic Surface bid items. - Special provisions that require placing mixture conforming to the contract requirements under 460 for HMA pavement or under 465 for asphaltic surface Cold Weather Paving Plan (1) Submit a written cold weather paving plan to the engineer at the preconstruction meeting. In that plan outline material, operational, and equipment changes for paving when the air temperature approximately 3 feet above grade, in shade, and away from artificial heat sources is less than 40 F. Include the following: - Use a department-accepted HMA mix design that incorporates a warm mix additive from the department's APL. Do not use a foaming process that introduces water into the mix. - Identify the warm mix additive and dosage rate. - Identify modifications to the compaction process and when to use them. (2) Engineer written acceptance is required for the cold weather paving plan. Engineer acceptance of the plan does not relieve the contractor of responsibility for the quality of HMA pavement placed in cold weather except as specified in (3). NOT FOR CONTRACT ADMINISTRATION Effective with the December 2017 Letting Standard Specifications

108 Cold Weather Paving Operations (1) Do not place asphaltic mixture when the air temperature approximately 3 feet above grade, in shade, and away from artificial heat sources is less than 40 F unless a valid engineer-accepted cold weather paving plan is in effect. (2) If the national weather service forecast for the construction area predicts ambient air temperature less than 40 F at the projected time of paving within the next 24 hours, confirm or submit revisions to the cold weather paving plan for engineer validation. Update the plan as required to accommodate the conditions anticipated for the next day's operations. Upon validation of the plan, the engineer will allow paving for the next day. Once in effect, pave conforming to the engineer-accepted cold weather paving plan for the balance of that work day or shift regardless of the temperature at the time of paving Preparing and Storing Mixtures (1) Heat and combine aggregate and asphaltic material to produce a mixture within the temperature range the mixture design specifies when discharged from the mixer. Mix until achieving a homogeneous mixture with uniformly coated aggregate. The contractor may store the mixture in silos Transporting and Delivering Mixtures (1) Deliver the mixture to the paver receiving hopper at a temperature within 20 F of the temperature the asphaltic material supplier recommends. Cover loads during inclement weather or when the ambient air temperature falls below 65 F. (2) If depositing asphaltic mixture on the roadway, provide equipment to pick up substantially all of the asphaltic mixture from the roadway and load it directly into the paver receiving hopper. Use either a device integral to the paver or intermediate transfer equipment Correcting Base (1) Before placing asphaltic base or surface courses, correct the existing pavement by filling potholes, sags, and depressions; altering the existing crown; or other corrections the engineer requires. Place asphaltic lower layer mixtures where and as the engineer directs. The contractor may hand place or use blade graders or mechanical spreaders to place mixture used for wedging, leveling layers, or filling holes. Feather the mixture out to become co-planar with adjoining areas and, unless the engineer directs otherwise, compact uniformly as specified in Spreading and Finishing Mixture (1) Place asphaltic mixtures in layers to the typical sections the plans show with self-propelled pavers. Pave at a constant speed, appropriate for the paver and mixture, that ensures uniform spreading and strike-off with a smooth, dense texture and no tearing or segregation. Do not pave faster than the average delivery rate of asphaltic mixture to ensure, as nearly as possible, continuous paving. (2) If placing the initial lane of a given layer, sense off a tight string line, a mobile string line, or a traveling straightedge whichever the engineer approves for the specific field conditions. On subsequent lanes of the layer, the contractor may sense off the adjacent lane surface. (3) Avoid raking over machine spread and finished material on surface courses to the extent possible to prevent segregation. (4) The contractor may spread material by hand in areas not accessible to pavers. Dump material outside the placement area, spread into place with shovels, and shape to the required grade and contour with rakes and lutes. Do not rake material from a pile of dumped material. (5) Do not haul over any portion of a placed layer until after the final rolling is complete on that portion. (6) If a longitudinal joint other than the notched wedge joint is constructed, place multi-lane pavement so that each day's placement in all lanes ends at the same station, unless the engineer directs or allows NOT FOR CONTRACT ADMINISTRATION otherwise Compaction General (1) Unless the contract specifies otherwise for the particular type of work, compact using the ordinary compaction procedure. After spreading and strike-off and while still hot, compact each layer thoroughly and uniformly by rolling. Roll during daylight hours unless providing artificial light the engineer finds satisfactory. Use the appropriate number of rollers to achieve the specified compaction, surface finish, and smoothness requirements. Ensure that the compacted surface is smooth and true to the established crown and grade. (2) Roll the entire surface until achieving the specified compaction and, to the extent practicable, eliminate roller marks. If turning or reversing the roller, or other operations, causes any scuffing or displacement, immediately correct the damage and revise the rolling procedure to prevent further damage. Keep Effective with the December 2017 Letting Standard Specifications

109 roller wheels moistened to keep mixture from sticking to them. Do not use excess water. Do not disturb the line and grade elevation of edges of the asphaltic pavement or surfacing. (3) Along forms, curbs, headers, walls, and at other places not accessible to the roller, compact the mixture thoroughly with hot hand tampers or mechanical tampers giving equivalent compression. On depressed areas, use a trench roller or other engineer-approved equipment. (4) Remove and replace material that is loose and broken, mixed with dirt, or is otherwise unacceptable with fresh hot mixture. Also remove and replace areas with excess asphaltic material. Compact replaced mixture immediately flush with the adjacent placement Ordinary Compaction (1) Unless the contract specifies otherwise, compact patching, leveling, and wedging layers of asphaltic pavement or surfacing; all layers of plant mixed asphaltic base and base widening; driveways; and other non-traffic areas until no further appreciable consolidation is visible under the action of the compaction equipment. Use 2 or more rollers per paver if placing more than approximately 165 tons of mixture per hour. (2) The engineer will assess the compacted density using the methods specified for the particular type of work Applying Tack Coat (1) Apply tack coat as specified in to each layer of a plant-mixed asphaltic base or pavement that will be overlaid with asphaltic mixture under the same contract Jointing (1) Place all layers as continuously as possible without joints. Do not roll over an unprotected end of freshly laid mixture unless interrupting placement long enough for the mixture to cool. If interrupting placement, ensure proper bond with the new surface. Form joints by cutting back on the previous run to expose the full depth of the layer. After resuming placement, place the fresh mixture against the joint to form intimate contact and be co-planar with the previously completed work after consolidation. (2) Where placing against existing HMA pavement, cut back the existing mat to form a full-depth butt joint. (3) Construct notched wedge longitudinal joints for mainline paving if the pavement thickness conforms to the minimums specified in , unless the engineer directs or allows an alternate joint. Taper each layer at a slope no greater than 12:1. Extend the taper beyond the normal lane width, or as the engineer directs. Ensure that tapers for all layers directly overlap and slope in the same direction. (4) Place a 1/2 to one inch vertical notch after compaction at the top of tapers on all layers. Place the finished longitudinal joint line of the upper layer at the pavement centerline for 2-lane roadways, or at the lane lines if the roadway has more than 2 lanes. (5) Construct the tapered portion of each layer using an engineer-approved strike-off device that will provide a uniform slope and will not restrict the main screed. Apply a weighted steel side roller wheel, as wide as the taper, to the tapered section. Compact the initial taper section to as near the final density as possible. Apply a tack coat to the taper surface before placing the adjacent lane. (6) Clean longitudinal and transverse joints coated with dust and, if necessary, paint with hot asphaltic material, a cutback, or emulsified asphalt to ensure a tightly bonded, sealed joint Surface Requirements (1) Test the surface at engineer-selected locations with a 10-foot straightedge or other engineer-specified device. Ensure that upper layers show no variation greater than 1/8 inch between any 2 surface contacts. Ensure that lower layers, shoulder surfacing, and surfacing on temporary connections and bypasses show no variation greater than 1/4 inch between any 2 surface contacts. (2) Remove and replace or otherwise correct, using engineer-approved methods, humps or depressions exceeding the specified tolerance Paving Shoulders (1) Conform to the other requirements under except, if constructing shoulders separately and the placement width is too narrow to accommodate the required pavers and rollers, the contractor may use engineer-approved alternate spreading and compaction equipment. Alternate equipment must be capable of satisfactorily laying mixture to the required width, thickness, texture, and smoothness Safety Edge SM NOT FOR CONTRACT ADMINISTRATION (1) Construct safety edge monolithically with and extending beyond the edge of pavements that have no paved shoulder, have paved shoulders 3 feet wide or less, and at other locations the plans show. Effective with the December 2017 Letting Standard Specifications

110 Safety edge is not required on edges that abut other HMA or concrete elements or where the engineer excludes for constructability issues. (2) Compact conforming to Ensure that after final rolling the safety edge angle is within the tolerances the plans show. The contractor may use full depth sawing to remove formed edges integrally placed with pavement where safety edge is not required. (3) Use a paver equipped with a wedge maker from the department's APL capable of constructing the specified edge cross-section. Do not use a single plate strike off. (4) Place the finished shoulder material to the top of the safety edge conforming to Maintaining the Work (1) Protect and repair the prepared foundation, tack coat, base, paved traffic lanes, shoulders, and seal coat. Correct rich or bleeding areas, breaks, raveled spots, or other nonconforming areas in the paved surface Measurement (1) The department will measure asphaltic mixtures by the ton of mixed aggregate and asphaltic material incorporated in the work unless the measurement subsection for a particular application specifies otherwise. Provide the engineer with weigh tickets showing the net weight of each load of material delivered. The department or department-authorized testing firms or agencies will test the contractor's truck, storage silo, or plant scales. (2) For minor quantities of mixtures and if the engineer approves, the contractor may report batch weights from plant scales as described in , instead of truck or storage silo scale weights. (3) The department will measure HMA Cold Weather Paving by the ton of HMA mixture placed conforming to an engineer-accepted cold weather paving plan Payment General (1) All costs of furnishing, maintaining, and operating the truck scale or other weighing equipment and furnishing the weigh tickets are incidental to the contract. (2) Nonconforming material allowed to remain in place is subject to price adjustment under (3) Full-depth sawing to remove integrally placed safety edge where not required is incidental to the contract. (4) The contractor is responsible for the quality of HMA placed in cold weather Cold Weather Paving (1) The department will pay for measured quantities at the contract unit price under the following bid items: ITEM NUMBER DESCRIPTION UNIT HMA Cold Weather Paving TON (2) Payment for HMA Cold Weather Paving is full compensation for additional materials and equipment specified for cold weather paving under including costs for preparing, administering, and following the contractor's cold weather paving plan. The department will not pay for HMA Cold Weather Paving for HMA placed as follows: - If the lot density is less than the minimum specified in table for mixture placed under On days when the department is assessing liquidated damages. (3) If because of an excusable compensable delay under , the engineer directs the contractor to pave when the temperature is less than 36 F for the upper layer or less than 32 F for lower layers, the department: - Will relieve the contractor of responsibility for damage and defects the engineer attributes to cold weather paving. - Will not assess disincentives for density or ride. (4) If HMA pavement is placed under and the HMA Cold Weather Paving bid item is not in the contract, the department will pay for the additional costs specified in (2) as extra work. The department will pay separately for providing HMA pavement and HMA surface under 460.5, 465.5, and the contract special provisions. NOT FOR CONTRACT ADMINISTRATION Effective with the December 2017 Letting Standard Specifications

111 TOPIC G: Asphalt Mixing Plants

112 TOPIC G: Asphalt Mixing Plants Page G-1 An HMA-TPC Technician should know the basic functions of a batch and drum mix facility operation. While conducting troubleshooting visits at the batch or drum mix facilities, the asphalt plant foreman should be notified by the HMA-TPC Technician of any problems that could be associated with the asphaltic mixture. The plant foreman has been trained to know almost every specific detail of the asphalt plant operation. Always work with the plant foreman on problems. Let him/her handle adjustments, check-ups, repairs and tuning. Again, remember to work out problems as a team. Please reference the Hot Mix Paving Handbook, Section 5

113 TOPIC G: Asphalt Mixing Plants Page G-2 Exercises on Asphalt Mixing Plants 1. How is the AC measured for a batch plant? 2. Where are the AC and hot aggregate mixed together in a batch plant? 3. How is the AC measured for a drum plant? 4. Where is the AC added in a drum plant?

114 TOPIC H: Process Control of Asphaltic Mixtures

115 TOPIC H: Process Control of Asphaltic Mixtures Page H-1 Process Control of Asphaltic Mixtures The HMA-TPC Technician is faced with two available options to begin troubleshooting an asphalt mixing plant. First of all, the asphalt mixture consists of aggregates, asphalt cement, and air voids. The process control of an asphalt mixing plant is divided into two types of problems: Aggregate gradation Asphalt content Aggregate Gradation Let s discuss aggregate gradation for a moment. examined carefully: There are three areas which need to be Stockpiles Stockpiles can be checked by analyzing the process control data from the stockpile as it was built or by sampling and testing the stockpile to obtain the gradation data. Cold feed A cold feed belt sample may be taken somewhere between the cold feed bins and the rotating drum/dryer for aggregate gradation determination. Extraction An extraction may be taken from the plant-produced asphaltic mixture to determine aggregate gradation. The extraction procedure should be performed in accordance with WisDOT Test Method for Solvent Extraction Gradation found in CMM The extraction gradation is of most importance because it relates to the end product. Once the gradation data has been collected from the stockpile, cold feed, and extraction by WisDOT 1560, the data can be analyzed as follows: Stockpile vs. Cold Feed Gradation Data Each stockpile gradation can be mathematically blended to identify the appropriate JMF. Once the JMF has been established in the stockpiles, then the JMF blend may be compared to the cold feed gradations. At this point, you may be able to identify a problem that may be affecting the asphaltic mixture, such as segregation, degradation, improper load-out, etc. Cold Feed vs. Extraction Gradation Data During a process control troubleshooting inspection, the cold feed sample of the blended aggregates should be sampled simultaneously with the plant-produced asphaltic mixture. Usually it is advisable to wait one hour after sampling the cold feed blended sample before sampling the asphalt extraction sample. Once the samples have been procured simultaneously, the aggregate gradations may be used to determine a correlation between the aggregate test data. For instance, you may notice a higher percentage fines in the extraction sample. Excessive fines in the extraction gradation could indicate:

116 TOPIC H: Process Control of Asphaltic Mixtures Page H-2 Degradation in rotating dryer/drum High input of mineral filler (if applicable) High input of baghouse dust Aggregate problem (too soft) Bin spillover in No. 8 chip bin Segregation Contamination Change of stockpile material Asphalt Content Process control problems may also be associated with the asphalt content in an asphaltic mixture. Sources of asphalt content information are developed from: Calculations using Gmm Nuclear gauge (optional) Nuclear Gauge The alternate method for determining the asphalt content is by nuclear gauge (optional method). Nuclear gauges are very expensive but produce very reliable results when properly calibrated.

117 TOPIC H: Process Control of Asphaltic Mixtures Page H-3 Significance of Gradation and Asphalt Content Gradation can affect: 1. Individual Sieve Percent Passing Each sieve percent passing must meet the specified JMF tolerances. As an HMA- TPC Technician, you may encounter a stockpile that has been depleted. The material supplier would like to deliver material from a pit two miles away which has a very similar gradation. CAUTION: Even though the material has a similar gradation, use of the material will probably result in a change of asphaltic mixture properties. The asphaltic mixture properties will be affected by: a. Change in crushing manufacturing process b. Change in particle shape VMA is affected by particle shape. c. Change in effective specific gravity, Gse A moderate change in the GSE value may indicate a material source change. 2. Test Results a. Bulk Specific Gravity, Gmb As the gradation moves away from the Maximum Density Line (MDL) Gmb decreases due to increased VMA. Inversely as gradation approaches the Maximum Density Line Gmb increases. b. Theoretical Maximum Specific Gravity, Gmm Gmm can be affected by gradation changes since different size elements in a blend may have significantly different Gsb. This is the reason we recalculate blended Gsb when aggregate blend percentage have been adjusted. 3. Volumetric Properties a. Voids in Mineral Aggregate, VMA VMA is a function of gradation, particle shape and asphalt content. If asphalt content and particle shape remain constant, as the gradation approaches the MDL inter-granular space is reduced resulting in a lower calculated VMA. b. Voids in Total Mix, Va (Air Voids) Air voids are defined as the VMA of compacted mixture that is not filled with asphalt. If asphalt content remains constant and VMA falls due to a change in gradation air voids will be reduced as well. 4. Performance Asphaltic Concrete performance can be affected by changes in gradation. Gradation changes that lead to high voids can cause the mix to be difficult to compact, high in place air voids allow the mix to remain permeable and the

118 TOPIC H: Process Control of Asphaltic Mixtures Page H-4 asphalt to age prematurely. High voids also contribute to rutting. Low voids can lead to excessive asphalt content and mixture that ruts or flushes.

119 TOPIC H: Process Control of Asphaltic Mixtures Page H-5 Asphalt content can affect: 1. Individual Sieve Percent Passing Asphalt content changes that are not accounted for when performing extraction using WisDOT 1560 can skew gradation calculations. Most notably the percent P#200 and a decrease in Asphalt Content may be misinterpreted as a decrease in P# Test Results a. Bulk Specific Gravity, Gmb As asphalt content increases, Gmb increases; inversely, as asphalt content decreases, Gmb decreases. b. Theoretical Maximum Specific Gravity, Gmm As asphalt content increases, then Gmm decreases: inversely, as asphalt content decreases, the Gmm increases. 3. Asphalt content will affect mixture characteristics by: a. Voids in Total Mixture, VTM A decrease in asphalt content, means an increase in air voids; inversely, an increase in asphalt content means a decrease in air voids. b. Voids in Mineral Aggregate, VMA With an increase in asphalt content, VMA decreases to a point and then as more asphalt is added VMA can increase. VMA decreases initially as asphalt is added due to reduced friction between the aggregate particles. Once the volume of asphalt exceeds the volume of the voids in the mineral structure, the asphalt crowds out aggregate and VMA will appear to increase. c. Performance Performance relies heavily on the percent air voids in the mixture and asphalt film thickness on the aggregate. Excessive in place air voids accelerates aging of the asphaltic mixture, leading to fatigue cracking. High voids can also be a contributing factor in pavement rutting. Proper asphalt content allows the mixture to be compacted readily in place, reducing the incidence of rutting and reducing the infiltration of air and water which can lead to loss of flexibility and adhesion of the binder. Overasphalting a mixture typically leads to low stability of the mixture and mixtures that will rut, shove, or bleed.

120 TOPIC H: Process Control of Asphaltic Mixtures Page H-6 EXERCISES INVOLVING PROCESS CONTROL OF ASPHALTIC MIXTURES Sources of Possible Problems in a Batch Mix Facility 1. Cold Feed Bin Spillover 2. Incorrect Calibration Percentage for Each Cold Feed Bin 3. Finer Material Sticking to Cold Feed Bin Gates 4. Cold Feed Bins Run Empty 5. Moisture Content of Aggregate Stockpile Aggregate material flows differently as moisture increases or decreases in stockpiles. For instance, a plant is calibrated with the material at 1.5 percent moisture content. During the night, three to four inches of rain fall. Stockpile samples should be taken and new aggregate moistures determined. The new moisture content of the same aggregate material is at 5.5 percent. The material will flow differently at a rate of 5.5 percent moisture content. The higher percent moisture content will influence the flow rate of the finer material the most. Since production operations are weight-based, if this increase in moisture is not properly accounted for, the result is adding more weight from water and therefore less weight of aggregate for a constant batch weight. 6. Slippage of Conveyor Belts Belts may loosen and cause feed problems. 7. Computer Control The environment of an asphalt plant is less than ideal for computer operation; dust, humidity, temperature variations, vibration and voltage fluctuation can all affect computer function. Errors can also occur in the entry of production parameters as well and should be considered. 8. Aggregate Scales Aggregate scales should be calibrated on the mixing platforms regularly. Scale zero should be noted daily as failure to return to zero can indicate several issues, failing load cells, blocked scales, etc. 9. Segregation Segregation is caused by improper load-out techniques, non-uniform feed on conveyor belts, change in moisture content levels of material and during unloading from silos, pugmills, trucks and pavers. 10. Sampling and Testing Errors These errors occur because of a failure to follow prescribed laboratory procedures, and temperatures. Double check all equipment and temperatures before making adjustments to the production process. Occasionally data entry and calculation errors can be misleading, use extreme care when entering test data.

121 TOPIC H: Process Control of Asphaltic Mixtures Page H-7 Sources of Possible Problems in a Drum Plant 1. Cold Feed Bin Spillover 2. Incorrect Calibration Percentage for Each Cold Feed Bin 3. Finer Material Sticking to Cold Feed Bin Gates 4. Cold Feed Bins Run Empty 5. Moisture Content of Aggregate Stockpile As noted above, aggregate flow rates can be affected by the moisture content of the aggregate. In the case of a drum mix plant moisture changes can also influence asphalt content if the change is not compensated for in the mix control system. 6. Slippage of Conveyor Belts Belts may loosen and cause feed problems. 7. Computer Control The environment of an asphalt plant is less than ideal for computer operation, dust, humidity, temperature variations, vibration and voltage fluctuation can all affect computer function. Errors can also occur in the entry of production parameters as well and should be considered. 8. Aggregate Scales Aggregate scales should be calibrated on the mixing platforms regularly. Scale zero should be noted daily as failure to return to zero can indicate several issues, failing load cells, blocked scales, etc. Asphalt is metered according to the aggregate weight from the belt scale, improper scale readings will lead to improper asphalt content. 9. Asphalt meters Improper calibration of the asphalt meter causes the mix to be over- or underasphalted. Signal wires from the meter to the blending system can be distorted by improper shielding of the cord from sources of electromagnetic interference. 10. Segregation Segregation is caused by improper load-out techniques, non-uniform feed on conveyor belts, change in moisture content levels of material and during unloading from silos, pugmills, trucks and pavers. 11. Sampling and Testing Errors These errors can occur because of a failure to follow prescribed laboratory procedures, and temperatures. Double check all equipment and temperatures before making adjustments to the production process. Occasionally, data entry and calculation errors can be misleading. Use extreme care when entering test data.

122 TOPIC H: Process Control of Asphaltic Mixtures Page H-8 Problems Associated with Aggregate Many problems associated with aggregates can be minimized by careful attention to handling and stockpiling the aggregates during production. It is a good idea before project start-up to know the method(s) of stockpile construction. Review the quality control/quality verification data to discover how uniformly each stockpile has been built. A stockpile built with no process control or test records may indicate a non-uniformly built stockpile. Additional sampling and testing may be required by the quality control team to verify uniformity. Stockpiles built in layers will help minimize segregation. The load out is another possible source of variability, whenever possible the loader should work perpendicular to the direction of flow for the stacking conveyor. The loader should work the entire face to minimize segregation. The cold feed system is responsible for metering the aggregates into the plant in the proper percentages. Care must be taken to calibrate the bins accurately so that the desired blend is achieved. Cold feed calibration is accomplished in two ways: 1. Gates Gates are used to restrict the opening of the bin. The gates should be adjustable and durable enough to maintain the desired opening. Once set, it is helpful to mark the gate in some way so that if it is moved for maintenance it will be possible to return it to near the original setting to speed recalibration. 2. Variable Speed Feeder Belts After the gate opening has been selected, based on the approximate percentage of the material desired from the individual bin, the feeder belt is run at speeds from maximum to minimum operational range. The rate of material delivered at each speed is determined and can be entered into the control system so that the proper amount of each aggregate is delivered into the drum.

123 TOPIC H: Process Control of Asphaltic Mixtures Page H-9 Factors or Causes Attributed to Aggregate Problems 1. Segregation This can occur at any time or anywhere on and off the project site. Try to minimize segregation by handling material properly. 2. Degradation This occurs as larger material breaks down into smaller sizes. Control degradation by alerting heavy equipment operators to stay off stockpiles or keep traffic minimal, if possible. Some degradation will occur in the mixing process and is unavoidable. 3. Contamination This usually occurs when the loader operator digs down too deep into the stockpile, carrying foreign material on tires onto stockpile and during cold feed bin spillover. 4. Improper Loading of Cold Feed Bins This consists of improper load-out procedure, loading of wrong material into cold feed bin(s), or loading causing bin spillover. 5. Gate/Flow Rate Feeder Calibration Be alert to changing moisture conditions in stockpiles. It is advisable to conduct percent aggregate moisture tests (AASHTO T-255 Standard Method of Test for Total Moisture Content of Aggregate by Drying) to monitor the percent moisture content in each stockpile. Remember, moisture content mainly affects finer aggregate stockpiles. 6. Moisture Excessive moisture causes problems with gate/flow rate feeder calibrations and also affects the drying time in the drum/dryer and the production rate (tons per hour). Improperly-dried aggregates during the drum/dryer process are attributable causes to the stripping and raveling problems associated with the asphaltic mixture. Factors Attributed to Production (Plant) Problems The responsibility of an HMA-TPC Technician is not to know every aspect of how asphalt mix facilities function but to be aware of problems which might exist. The responsibility of the HMA-TPC Technician involves communication with the QC team to resolve process control problems. Again, always work with the plant foreman in solving production (plant) problems. DO NOT repair or make any physical adjustments yourself.

124 TOPIC H: Process Control of Asphaltic Mixtures Page H-10 Let s discuss some common production (plant) problems: 1. Equipment Wear Batch Plant Screens, chutes, and bins in the hot tower. Batch/Drum Worn Flights inside the dryer/drum can lead to improper mixing, poor heat transfer, and poor drying of aggregate. 2. Equipment Malfunction Drum Plant The weigh scale on the conveyor belt does not operate correctly if the conveyor belt slips, so be aware! Load Cell A load cell is a device used in the weighing process. Improper aggregate/asphalt weights before the mixing process will cause process control problems. 3. Electronics Lightning High towers at asphalt plants are prime candidates for lightning strikes. Lightning strikes have affected the operation of the computer. Make sure all towers have been properly grounded. Causes Attributed to Production (Plant) Problems: 1. Poor Maintenance Proper preventive maintenance of equipment may prevent plant equipment problems. Regular inspection and effective communication of observed potential problems is fundamental to a solid preventative maintenance program. 2. Lack of Proper Control Poor communication of sample data makes it impossible to respond to issues as they arise. Failure to respond to problems in a timely fashion can make major issues out of minor deviations. 3. Lack of Understanding Keep all team members informed of specifications and penalties assessed for not complying with specification requirements. A misinformed or confused team member could be a process control problem. The key word is team.

125 TOPIC H: Process Control of Asphaltic Mixtures Page H-11 Factors Attributed to Equipment-Related Problems: 1. Causes in Batch Plant a. Aggregate Scales If the weight of the aggregate varies up or down, this phenomenon will affect the percent asphalt content. The plant foreman should check aggregate scales calibration regularly. b. AC Scales Regularly calibrate AC scale and check asphalt weight bucket to make sure it moves freely. c. Leaking Valves A common process control problem is caused by a leaky or clogged asphalt valve or line. 2. Causes in Drum Mix Facility a. Aggregate Belt Scales Aggregate belt scales may be out of adjustment or slipping, and excess fine material buildup may affect the weigh scale capability. Excess buildup on the belt is attributed to moisture conditions. Both of these conditions will overestimate aggregate quantities. b. Asphalt Meter Calibration The asphalt meter is calibrated by pumping a certain amount of asphalt into a tanker and then weighing the tanker and recording the asphalt cement temperature. Improper temperatures or binder specific gravity will affect asphalt content. Be aware: some asphalt flow meters will measure air as asphalt. For example, at the end of a project, a plant foreman would like to empty the asphalt storage unit so that he/she does not have to pump out the asphalt cement. While trying to empty the asphalt storage unit, the foreman may inadvertently measure air near the bottom of the unit, and false readings in measuring may occur. c. Incorrect Moisture Correction It is very important to monitor the actual moisture content (AASH90 T 255- Total Moisture Content of Aggregate by Drying). It is critical that the actual moisture correction factor be dialed into the plant computer. Improper moisture correction factor will cause process control problems with asphalt content and affect the asphaltic mixture properties. If the moisture content is too high and adjustments have not been made on the scale, then a portion of that water will appear as aggregates. This condition will produce low total voids in the mixture (high AC). Inversely, if the moisture content is estimated, this will reduce the quantity of asphalt added, and the voids in the total mixture will increase (low AC).

126 TOPIC H: Process Control of Asphaltic Mixtures Page H Problems Common to All Plants a. Wrong Type of Asphalt Cement The specific gravity of the different types of AC will change and have a direct effect on the asphaltic mixture properties. b. Mixture Temperature If you witness blue smoke from an asphaltic mixture, the mix temperature is too high. Also, too high an asphalt mix temperature will burn off and reduce the asphalt film thickness. The asphalt film thickness affects the performance life of the asphalt mixture. Low asphalt mix temperature will affect coating of the aggregate particle and reduce the ability to achieve proper compaction causing poor pavement performance. c. Electronics d. Sampling and Testing Aggregate Diagnostic Problems Gradation a. If individual sieve is off specifications: Check Control Charts for Mixture Properties For example: Air Voids If air voids within limits, adjust tolerance for individual sieve and ask for JMF change. If air voids outside limits, look for causes. b. Causes of off tolerance gradation Cold feed gradation (stockpile/belt) Moisture in fine aggregates Equipment wear Flow rate/scales Sampling and testing

127 TOPIC H: Process Control of Asphaltic Mixtures Page H-13 Gradation Variabilities Checklist 1. Aggregate Stockpiling New added material Changes at source Segregation during hauling or stockpiling Sampling and testing errors 2. Belt Samples Variation in stockpiling Segregation of aggregate Improper loading of cold feed bins Improper setting of individual cold feed bins Sampling and testing errors 3. Hot Bins Improper cold feed setting Erratic feed from dust-collecting system Changing production rate (screening efficiency) Blinding screens Holes in screen or bin walls Sampling and testing errors 4. Asphaltic Mixtures Sample location Truck Back of paver Causes of variability Incorrect hot bin gradations Incorrect percentages Segregation in truck or silo

128 TOPIC H: Process Control of Asphaltic Mixtures Page H-14 Mixture Diagnostic Problems 1. Total Mixture Voids - Air Voids, % 2. Low Air Voids Most important physical property If too high -- If too low -- Causes Gradation P-200 High asphalt content Corrections Check gradation Check P-200 Check asphalt metering/scales 3. High Air Voids Causes Incorrect moisture content Segregation Incorrect asphalt content Corrections Compare actual and used moisture contents Check gradation -- perform extraction Calculate percent AC and/or check metering/scales Change in Maximum Specific Gravity, Gmm, Indicates 1. Asphalt content 2. Aggregate gradation 3. Specific gravity 4. Absorption 5. Sampling and testing

129 TOPIC H: Process Control of Asphaltic Mixtures Page H-15 Process Control Problem Solving Using A Flow Chart Process control problem solving using a flow chart can be a very useful trouble-shooting tool. A flow chart is a methodical approach, which organizes the way to handle or solve a problem. QC Data approaching warning band No Are Va and VMA Acceptable? Yes Has Gmm changed? No Is Gradation Acceptable? Yes es Yes No Moisture change? Correct. Yes No No Yes No No No Are Agg Scales functioning properly? Yes Is asphalt usage correct? Recalibrate meter or Weigh Pot. Has Gmb Changed? Yes OK Check Calculations. Check agg Gravities Absorption FAA CAA Yes Check: Has source changed? Batch or Drum Plant? New Crushing? Drum Batch Stockpile Gradations Gate Settings Blend % s Bin per agg Check: Stockpile Gradations Gate SettingsBlend % s Bin per agg Hot draws Hot bin gradation Hot Screens

130 TOPIC H: Process Control of Asphaltic Mixtures Page H-16 Exercise on Asphalt Mixing Facility 1. Who is responsible for making asphaltic mix adjustments at the asphalt mixing plant?

131 TOPIC I: Troubleshooting Mixtures, Sampling and Testing, and Asphalt Problems

132 TOPIC I: Troubleshooting Mixtures, Sampling & Testing Page I-1 Sampling and Testing Errors in Aggregate 1. Improper Conveyor Belt Sample Technique For example, a certified AGGTEC-I may be sampling off the stopped conveyor belt and be using a paint scraper to remove all fine material which has built up on the conveyor belt over time. The excess fine material scraped from the conveyor belt may have been the leading cause of the process control problem. The sampling problem will be solved by communicating to the certified AGGTEC-I to observe the underside of the belt and use only a fine brush to remove material from the conveyor belt. 2. Improper Test Sample Size Check to make sure aggregate samples have been procured by using the specified nominal maximum particle size definition. Refer to WisDOT Sample Size By Nominal Maximum Particle Size (CMM ). 3. Overloading of Sieves on Gradation Analysis Overloading of a sieve will cause a gradation test analysis to be unacceptable. Each sieve must conform to the specified maximum allowable weight. Refer to WisDOT Maximum Weight of Material Allowed on Sieves (CMM ). 4. Improper Gradation Analysis Calculation Always double-check calculations before alerting anyone of any process control problems. Sometimes a miscalculation may be all that is wrong. 5. Calibration and Condition of Scales Always check weigh scales periodically. A weigh scale may be checked by using a calibration weight. 6. Improper Riffle Splitting Technique A rectangular sampling receptacle shall be used to feed the sample through the riffle splitter. A riffle splitter shall be clean and free of particles which may contaminate the sample. 7. Not Adhering to Prescribed Sampling and Testing Procedures Short cuts or unapproved sampling and testing methods are violations of the specifications. Sampling and testing methods must be conducted by the prescribed procedure(s) which conform to project specifications.

133 TOPIC I: Troubleshooting Mixtures, Sampling & Testing Page I-2 Sampling and Testing Problems Associated with Asphaltic Mixtures 1. Sampling Errors Obtaining incorrect sample sizes is the most common sampling error. Always check to make sure at least the minimum specified sample weights have been procured. Also, improper quartering technique may induce segregation into the asphalt mixture. It is vitally important that all asphaltic mixture samples have been properly prepared and are stored in a dry area for the specified time period. Improperly stored and prepared retained samples will affect the results of the quality verification (QV) team. 2. Equipment Calibration a. Theoretical Maximum Specific Gravity (Gmm) Apparatus First, make sure oil level is okay and change oil whenever oil appears a milkywhite color. Second, air leaks in system hoses, hose connections, and leaky valves will cause improper vacuum. Third, check manometer to ensure it has a valid calibration. Fourth, the Gmm apparatus should be calibrated periodically. Finally, check to see if there is a screen over the pycnometer vacuum connection. This screen will aid in preventing material from being trapped in the vacuum lines. b. Scales Most electronic balances are heat sensitive, and a balance may weigh differently if exposed to a range of temperatures. Sometimes electronic balances drift, not weighing the same every time. Scale calibration should be performed periodically at least once before project start-up. Use certified standard calibration weights for calibration. Certified standard calibration weights should be checked annually. Certified calibration weights should be handled with special gloves that come with the weights. If you use your fingers to handle the certified calibration weights, oil residue from your fingers will allow the calibration weight to pick up dust or material particles and affect calibration. c. Temperature Most problems in testing can be related to temperature. Calibration shall include thermometers and ovens. Also, check waterbaths to make sure they conform to the specified temperatures, and check circulating pumps to ensure they are providing uniform water temperatures.

134 TOPIC I: Troubleshooting Mixtures, Sampling & Testing Page I-3 3. Calculation Error Always double-check your calculations. It is a good idea to have someone else check your work as well. Never alert anyone to a process control problem until all calculations have been rechecked. Remember, whenever equipment is calibrated, make sure it is documented, posted, and part of the project records. Factors Affecting Maximum Specific Gravity, Gmm 1. Increase in asphalt content 2. Aggregate gradations 3. Specific gravity/absorption of aggregates Exceeding Allowable Differences On Test Results Differences between the contractor's and engineer's split sample test results will be considered acceptable if within the following limits: Item Allowable Differences Sieve - percent passing 12.5 mm mm mm mm μm μm 2.0 Bulk Specific Gravity of the compacted mixture Maximum Specific Gravity 0.020

135 TOPIC I: Troubleshooting Mixtures, Sampling & Testing Page I-4 If comparison test results are outside the above allowable differences, the engineer will investigate the reason immediately. The engineer may stop production while the investigation is in progress if the potential for a pavement failure is present. The engineer's investigation may include testing of the remaining split samples, review and observation of the contractor's testing procedures and equipment, and a comparison of split sample test results by the contractor quality control laboratory, WisDOT quality verification laboratory, and the Bureau of Technical Services. If reasons for the differences cannot be determined, the engineer's results will be used for the quality control data, and the appropriate payment for the mixture and asphalt will be based on the procedures specified. The engineer will periodically witness the sampling and testing being performed by the contractor. If the engineer observes that the sampling and quality control tests are not being performed in accordance with the applicable test procedures, the engineer may stop production until corrective action is taken. The engineer will notify the contractor of observed deficiencies promptly, both verbally and in writing. The engineer will document all witnessed sampling and testing. If a difference exists between the contractor and the engineer, the Bureau of Technical Services will be asked to advise on the proper sampling and testing procedure. Calculations Using Theoretical Maximum Specific Gravity, Gmm As per WisDOT specifications, calculation of asphalt content begins on the second day of production. Asphalt content is calculated from the mixture Gmm, specific gravity of the binder (Gb) and aggregate specific gravity (Gse). (Asphalt content is calculated and reported to two decimal places.) Determination of aggregate specific gravity, Gse, is the volume of the aggregates including all the aggregate internal void spaces except those that absorb asphalt. Calculations of Gse: Where: Pb = Percent asphalt binder (measured in accordance with CMM 8-36) Gb = Specific gravity of asphalt binder (from the mix design) Gmm = Daily average

136 TOPIC J: Process Control Relationships

137 TOPIC J: Process Control Relationships Page J-1 Control Charts The control chart is a visual aid used to measure the variability of a process. Today, most agencies specify color codes and assign values to specify the desired quality parameters. As an HMA-TCP Technician, you must possess the skills to analyze and interpret data by examining control chart trend relationships. Shown below is a model of a control chart: Upper Control Limit (UCL) Upper Warning Band Upper Warning Limit (UWL) Target Lower Warning Limit (LWL) Lower Warning Band Lower Control Limit (LCL) Specifications state the test results obtained by the contractor shall be recorded on the control charts the same day the tests are conducted. It is very important so that trends may be analyzed as soon as process control data become available. Gradation Master Band The HMA-TPC Technician s occupational responsibility is to monitor, analyze, and make necessary asphaltic mixture adjustments to satisfy the parameters of the specifications. As long as trends are between the JMF and warning limits, no significant changes or adjustments are required. Before any necessary process control adjustments are to be made, make sure all data have been thoroughly analyzed. Job Mix Formula (JMF) adjustment may be necessary on the No. 8 sieve. The JMF limits for a 12.5 mm mixture on the No. 8 sieve are between 28 and 58 percent passing. The current No. 8 sieve running average is at 58 percent. The new JMF limit shall not exceed the gradation master band of either 28 or 58 percent. However, the JMF tolerances may exceed the gradation master band. The new JMF limit target is at 58 percent. Refer to Figure 10.1 Gradation Master Band illustration UCL UWL 58.0 New JMF Target = 58% Target LWL LCL Figure Gradation Master Band Illustration

138 TOPIC J: Process Control Relationships Page J-2 Documentation WisDOT standard specification states, The contractor shall be responsible for documenting all observations and records of inspection, adjustments to the mixture, and test results on a daily basis. Results of observations and records of inspection shall be noted in a permanent field record as they occur. All process adjustments and job mix formula changes shall be noted on the air void chart. Copies of the running average calculation sheet for blended aggregate, mixture, and asphalt content along with the air void chart and records of adjustment shall be provided to the engineer in a neat and orderly manner within ten days after the completion of paving. Relationships of Asphaltic Mixture Properties Specific Gravity The voids in total mixture (VTM) is the most important asphaltic mixture property related to performance. Three common test procedures used for determining VTM: 1. Compaction of specimen, AASHTO T Bulk specific gravity of compacted bituminous paving mixtures using saturated surface-dry specimens, AASHTO T Rice maximum specific gravity of bituminous paving mixtures, AASHTO T 209 The bulk specific gravity (Gmb) is determined by AASHTO T 312 and AASHTO T 166. The Gmb consists of three ingredients: air, asphalt, and aggregate. Bulk Specific Gravity, Gmb 150 mm A A = B = C = Volume of air Volume of asphalt Volume of aggregate Gmb includes A + B + C 115 mm +/-5 mm The Gmb specimen is 150 mm in diameter and 115 mm +/- 5mm in height. The Gmb is measuring the weight/volume relationship or specific gravity of each ingredient involved in the asphaltic mixture. In an examination of Gmb volume relationships, the aggregates are the most predominant factor and affect the results of the Gmb the most. The inverse is true regarding air and asphalt. Gmb relates volume of air plus volume of asphalt plus volume of aggregates to total weight. B C

139 TOPIC J: Process Control Relationships Page J-3 The theoretical maximum specific gravity (Gmm) is determined by the rice maximum specific gravity of bituminous paving mixture procedure, AASHTO T 209. The Gmm includes two ingredients: aggregates and asphalt. Theoretical Maximum Specific Gravity, Gmm B = Volume of asphalt C = Volume of aggregate A = Volume of air = 0 B C Gmm includes B + C The Gmm measures the weight/volume relationship or specific gravity of the asphalt and aggregates in a voidless state. Again, aggregates are the predominant influence on the Gmm asphaltic mixture property. Gmm relates volume of aggregate plus volume of asphalt to the combined weight. % Voids = [(Gmm - Gmb) / Gmm ] x 100 The percent VTM is determined by the relationship of Gmm minus Gmb, divided by Gmm, multiplied by 100. The percent voids measures volume of air in the following: Compacted specimen (laboratory of field voids) Cores (roadway voids) Determination of percent density is Gmb divided by Gmm, multiplied by 100. % Density = (Gmb/Gmm) x 100

140 TOPIC J: Process Control Relationships Page J-4 Asphaltic Mixture Property General Guidelines percent change in (-) P-200 material generally creates about a 1.0 percent change in voids. 2. Too much or not enough (-) P-200 material creates a tender asphaltic mixture. 3. A sandy mix (very fine on the No. 8 sieve) may create a tender asphaltic mixture. 4. Too high a percentage of material passing No. 30 sieve can create a tender asphaltic mixture (sand or camel hump). 5. Segregation of a sample can correlate to the asphalt content being high or low for an individual test. 6. Mat temperature for breakdown rolling should be 285 ± 15 o Fahrenheit. Finish rolling should occur at about 120 o Fahrenheit or cool enough to place your hand on the mat and leave it. Predetermined Proportionality Rules for Asphalt Mixture Properties Aggregate gradations trending down indicates coarser mixture. Aggregate gradations trending up indicates finer mixture. A coarser mixture relates to lower VMA. (Relative to max density line.) A finer mixture relates to higher VMA. (Relative to max density line.) Gmm (goes down) then % AC (goes up) Gmm (goes up) then % AC (goes down) Gmb (goes down) then % AC (goes down) Gmb (goes up) then % AC (goes up) If AC stays the same, gradation No. 8 to No. 200 (goes down) then VTM (goes down) If AC stays the same, gradation No. 8 to No. 200 (goes up) then VTM (goes up) Gmb (goes down) and AC (Constant) then P-200 (goes down) Gmb (goes up) and AC (Constant) then P-200 (goes up) Use caution. All proportionality rules are theoretically-based mathematical concepts. In reality, things may happen without justification of the proportionality rules.

141 TOPIC J: Process Control Relationships Page J-5 PROCESS CONTROL RELATIONSHIP EXERCISE A A trend on a control chart is the first visual indicator that a possible asphaltic mixture problem is occurring. Exercises A through D have been designed to demonstrate how the analysis of process control trends can be used to solve asphaltic mixture properties. 1. Refer to Figure 10.1, Process Control Relationship Exercise A. Identify all trends represented by the aggregate gradations and list below. 2. Refer to Figure , Process Control Relationship Exercise A. List and identify trends for each asphaltic mixture property; Gmb, Gmm, VMA, VTM, and % AC. Gmb Gmm VMA VTM % AC 3. What conclusions can be drawn from analyzing the trends from questions 1 and 2? Proportionality Rules Aggregate gradations trending down indicates coarse mixture. Aggregate gradations trending up indicates fine mixture. If Gmm (goes down) then % AC (goes up) If Gmm (goes up) then % AC (goes down) If Gmb (goes down) then % AC (goes down) If Gmb (goes up) then % AC (goes up)

142 TOPIC J: Process Control Relationships Page J-6 By analyzing the trends, you find: 4. What are the typical causes attributed to low asphalt content in a batch and drum plant? List causes common to both plants. Batch Plant: Drum Plant: Common to Both Plants:

143 TOPIC J: Process Control Relationships Page J-7 PROCESS CONTROL RELATIONSHIP EXERCISE A ANSWERS 1. Aggregate gradations are okay and within warning limits. 2. Gmb is trending down Gmm is trending up VMA is trending up VTM is trending up % AC is trending down 3. Aggregate gradation is okay, within warning limits Gmb is trending down (Gmb goes down = % AC goes down) Gmm is trending up (Gmm goes up = % AC goes down) % AC is trending down Conclusion: The Gmb, Gmm, VTM, and % AC trends indicate low % AC. The aggregate gradation is okay, within warning limits. All trends indicate low % asphalt content. 4. Batch Plant Aggregate scales AC scales Leaking valves or clogged line Drum Plant Aggregate belt scales Asphalt meter calibration Incorrect moisture correction Common to Both Plants Wrong type of AC Asphalt mixture temperature Electronics Sampling and testing (calculations)

144 TOPIC J: Process Control Relationships Page J-8 PROCESS CONTROL RELATIONSHIPS EXERCISE B 1. Refer to Figure 10.2, Exercise B - Process Control Relationships. Identify all trends represented by the aggregate gradations and list below: 2. Refer to Figure , Exercise B - Process Control Relationships. List and identify trends for each asphaltic mixture property: Gmb, Gmm, VMA, VTM, and % AC. Gmb Gmm VMA VTM % AC 3. What conclusions can be drawn from analyzing the trends from questions 1 and 2? Proportionality Rules Aggregate gradations trending down indicates coarse material. Aggregate gradations trending up indicates fine material. If Gmm (goes down) then % AC (goes up) If Gmm (goes up) then % AC (goes down) If Gmb (goes down) then % AC (goes down) If Gmb (goes up) then % AC (goes up)

145 TOPIC J: Process Control Relationships Page J-9 By carefully analyzing the trends, you find: 4. What are typical causes attributed to coarse aggregate being fed into a batch and drum plant? Batch Plant: Drum Plant:

146 TOPIC J: Process Control Relationships Page J-10 PROCESS CONTROL RELATIONSHIP EXERCISE B ANSWERS 1. All gradations are trending downward, which indicates a coarse mixture. (Refer to proportionality rules.) 2. Gmb is trending up Gmm is trending down VMA is trending down VTM is trending down % AC is okay 3. Aggregate gradation is trending coarser Gmb is trending up Gmm is trending down VMA is trending down VTM is trending down % AC is okay Conclusion: May indicate a change in aggregate source or a problem with sand in the cold feed bin. 4. Batch Plant: Improper load-out procedure Cold feed bin spillover (coarser aggregates in fine bin) Incorrect calibration/percentage for each cold feed bin Change in aggregate stockpile material Sand bin is near empty Wet material - change in flow rate Material sticking in gates Sampling and testing errors - calculations Visual inspection Drum Plant: Problems are similar to batch plant

147 TOPIC J: Process Control Relationships Page J-11 PROCESS CONTROL RELATIONSHIP EXERCISE C 1. Refer to Figure 10.3, Exercise C - Process Control Relationship. Identify all trends listed by the aggregate gradations and list below: 2. Refer to Figure , Exercise C - Process Control Relationship. List and identify trends for each asphaltic mixture property: Gmb, Gmm, VMA, VTM, and % AC. Gmb Gmm VMA VTM % AC 3. What conclusion can be drawn from analyzing the trends from questions 1 and 2? Proportionality Rules Aggregate gradations trending down indicates coarser material. Aggregate gradations trending up indicates finer material. The coarser the mixture, the lower VMA The finer the mixture, the higher VMA If Gmm (goes down) then % AC (goes up) If Gmm (goes up) then % AC (goes down) If Gmb (goes down) then % AC (goes down) If Gmb (goes up) then % AC (goes up) If AC stays the same, then gradation No. 8 - No. 200 (goes down) then VTM (goes down) If AC stays the same, then gradation No. 8 - No. 200 (goes up) then VTM (goes up) By carefully analyzing the trends, you find:

148 TOPIC J: Process Control Relationships Page J-12 PROCESS CONTROL RELATIONSHIP EXERCISE C ANSWERS mm (No. 4) and 2.36 mm (No. 8) gradations are trending downward indicating coarse material. 2. Gmb is trending down Gmm is trending down VMA is trending down VTM is trending down % AC is okay mm (No. 4) and 2.36 mm (No. 8) gradations are trending downward, indicating coarse material. Gmb is trending down Gmm is trending down VMA is trending down VTM is trending down % AC is okay Conclusion: VMA and VTM are within specification limits, and % AC is okay. A cold feed bin percentage change may be necessary to solve the coarse 4.75 mm (No. 4) and 2.36 mm (No. 8) material problem.

149 TOPIC J: Process Control Relationships Page J-13 PROCESS CONTROL RELATIONSHIP EXERCISE D - PART 1 1. Refer to Figure 10.4, Exercise D - Part 1 - Process Control Relationship. Identify all trends represented by the aggregate gradations and list below. 2. Refer to Figure , Exercise D - Part I - Process Control Relationship. List and identify trends for each asphaltic mixture property; Gmb, Gmm, VMA, VTM, and % AC. Gmb Gmm VMA VTM % AC 3. What possible conclusions can be drawn from analyzing the trends from questions 1 and 2? Carefully analyzing the trends, you find:

150 TOPIC J: Process Control Relationships Page J-14 PROCESS CONTROL RELATIONSHIP EXERCISE D - PART 1 ANSWERS 1. All gradations are trending upward, indicating a finer mixture. 2. Gmb is trending down Gmm is trending up VMA is trending up VTM is trending up % AC is trending down 3. Aggregate gradations are trending upward, indicating a finer mixture. Gmb is trending downward Gmm is trending upward VMA is trending upward VTM is trending upward % AC is trending downward Possible Conclusion: Exercise D - Part 1 indicates more than one solution may be needed to satisfy the asphalt mixture property parameters. During problem-solving determination, always try one method of adjustment to ensure you use the process of elimination to resolve a problem. Trying to solve a problem using multiple solutions will confuse the problem-solving process.

151 TOPIC J: Process Control Relationships Page J-15 PROCESS CONTROL RELATIONSHIP EXERCISE D - PART 2 1. Use the aggregate trends from Figure 10.4, Exercise D-Part 1 - Process Control Relationship. Use Figure , Exercise D-Part 2-Process Control Relationship to identify trends for each asphaltic mixture property: Gmb, Gmm, VMA, VTM, and % AC. Gmb Gmm VMA VTM % AC Possible Solution: PROCESS CONTROL RELATIONSHIP EXERCISE D-PART 2 ANSWERS 1. Gmb is trending downward Gmm is trending downward VMA is trending upward VTM is trending downward % AC is trending upward Possible Solution: VMA is trending high, VTM is trending very low, and % AC is trending really high. Adjusting the % AC should be the last alternative in solving an asphaltic mixture problem. The % AC in the mixture is necessary to facilitate a durable asphalt film thickness to instill pavement durability, although too much % AC in a mixture could cause bleeding and be detrimental to an asphaltic mixture. In this example, lowering the % AC may be the solution.

152 TOPIC K: Process Control Relationship Problems

153 TOPIC K: Process Control Relationship Problems Page K-1 PROBLEM # 1 - PROCESS CONTROL 1. Refer to Figures through , Problem #1 - Process Control. Identify all trends represented by the aggregate gradations and list below. 2. Refer to Figures through , Problem #1 - Process Control. List and identify trends for each asphaltic mixture property: Gmb, Gmm, VMA, VTM, and % AC. Gmb Gmm VMA VTM % AC 3. What conclusions can be drawn from analyzing the trends from questions 1 and 2? By analyzing the trends, you find: 4. What are the typical causes attributed to: Batch Plant: Drum Plant: Other:

154 TOPIC K: Process Control Relationship Problems Page K-2 PROBLEM # 2 - PROCESS CONTROL 1. Refer to Figures through , Problem #2 - Process Control. Identify all trends represented by the aggregate gradations and list below. 2. Refer to Figures through , Problem #2 - Process Control. List and identify trends for each asphaltic mixture property: Gmb, Gmm, VMA, VTM, and % AC. Gmb Gmm VMA VTM % AC 3. What conclusions can be drawn from analyzing the trends from questions 1 and 2? By analyzing the trends, you find: 4. What are the typical causes attributed to: Batch Plant: Drum Plant: Other:

155 TOPIC K: Process Control Relationship Problems Page K-3 PROBLEM #3 PROCESS CONTROL 1. Refer to Figures through , Problem #3 - Process Control. Identify all trends represented by the aggregate gradations and list below. 2. Refer to Figures through , Problem #3 - Process Control. List and identify trends for each asphaltic mixture property: Gmb, Gmm, VMA, VTM, and % AC. Gmb Gmm VMA VTM % AC 3. What conclusions can be drawn from analyzing the trends from questions 1 and 2? By analyzing the trends, you find: 4. What are the typical causes attributed to: Batch Plant: Drum Plant: Other:

156 TOPIC K: Process Control Relationship Problems Page K-4 PROBLEM # 4 - PROCESS CONTROL 1. Refer to Figures through , Problem #4 - Process Control. Identify all trends represented by the aggregate gradations and list below. 2. Refer to Figures through , Problem #4 - Process Control. List and identify trends for each asphaltic mixture property: Gmb, Gmm, VMA, VTM, and % AC. Gmb Gmm VMA VTM % AC 3. What conclusions can be drawn from analyzing the trends from questions 1 and 2? By analyzing the trends, you find: 4. What are the typical causes attributed to: Batch Plant: Drum Plant: Other:

157 TOPIC K: Process Control Relationship Problems Page K-5 PROBLEM # 5 - PROCESS CONTROL 1. Refer to Figures through , Problem #5 - Process Control. Identify all trends represented by the aggregate gradations and list below. 2. Refer to Figures through , Problem #5 - Process Control. List and identify trends for each asphaltic mixture property: Gmb, Gmm, VMA, VTM, and % AC. Gmb Gmm VMA VTM % AC 3. What conclusions can be drawn from analyzing the trends from questions 1 and 2? By analyzing the trends, you find: 4. What are the typical causes attributed to: Batch Plant: Drum Plant: Other:

158 TOPIC K: Process Control Relationship Problems Page K-6 PROBLEM # 6 - PROCESS CONTROL 1. Refer to Figures through , Problem #6 - Process Control. Identify all trends represented by the aggregate gradations and list below. 2. Refer to Figures through , Problem #6 - Process Control. List and identify trends for each asphaltic mixture property: Gmb, Gmm, VMA, VTM, and % AC. Gmb Gmm VMA VTM % AC 3. What conclusions can be drawn from analyzing the trends from questions 1 and 2? By analyzing the trends, you find: 4. What are the typical causes attributed to: Batch Plant: Drum Plant: Other:

159 APPENDIX 1: Answers to Student Problems, Mechanics of Mix Design & Recycling

160 Appendix 1: Page 1-1 TOPIC: Standard Specifications WisDOT Standard Specifications 1. Where would one find the aggregate master gradation requirements and production control limits? Table & standard spec In what instances is the contractor required to stop mixture production? When two consecutive running average values exceed the warning limit 3. What payment reduction percentage is applied to air voids produced within the warning bands? Pay is at 70% of contract price WisDOT Standard Specifications 1. What is the maximum percentage wear loss at 500 revolutions for an MT mixture? 45% 2. What is the minimum FAA requirement for an HT mixture? What is the minimum percent VMA for a #4 (12.5mm) HT mixture? 14.0% (may be changing)

161 Appendix 1: Page 1-2 Asphaltic Mix Design 1. What are the most important factors in predicting asphaltic mixture performance? Percent Air Voids and Compaction 2. What should the in-place air voids be for an HT mixture? 93.0% of the target maximum density 3. Air voids between and % after two to three years of traffic loading will provide optimum pavement performance. 2% and 4% 4. The higher the FAA, the higher the. The higher the voids between the fine aggregate particles. The higher the void content, the more angular the fine aggregate is. Asphalt Mixing Plants 1. How is the AC measured for a batch plant? Based on the aggregate batch size setting (2-6 ton) and pumped to a separate heated weigh bucket. 2. Where are the AC and hot aggregate mixed together in a batch plant? Pugmill 3. How is the AC measured for a drum plant? By metering (continuous delivery usually set as a gallon/minute based on aggregate tons/hour) 4. Where is the AC added in a drum plant? Direct injection into the drum

162 Appendix 1: Page 1-3 Mechanics of Mix Design Mixture Characteristics: The materials presented in this section are related to dense-graded hot-mixed asphalt concrete. In a hot mix asphalt paving mixture, asphalt and aggregate are blended together in precise proportions. The proportions of these materials determine the physical properties of the mix and how the mix will perform as a finished product. In order for hot-mix asphalt concrete to function well, it must be designed, produced, and placed to give it certain required properties: - Stability - Durability - Impermeability - Workability - Flexibility - Fatigue Resistance - Skid Resistance Stability is the ability to resist distortions. Stability specifications should be high enough to handle traffic adequately. Factors influencing stability are: 1. Internal Friction o Shape o Texture o Gradation 2. Cohesion o Film Thickness o Viscosity Durability is the ability to resist changes in the asphalt, degradation of aggregate, and stripping of asphalt film. These factors result from weathering and/or traffic. Durability is improved by: 1. Using maximum asphalt content 2. Using densely-graded aggregate with stripping-resistance 3. Compacting the mixture for minimum permeability Impermeability is the resistance of a mix to the passage of air and water into or through it. Virtually all asphalt mixtures used in highway construction are permeable to some degree. Workability is the case of placing and compaction. Workability is greatly affected by gradation. Mixtures which are too easily worked are referred to as tender mixes and are susceptible to distortion.

163 Appendix 1: Page 1-4 Flexibility is the ability to adjust to gradual settlements and movement in the subgrade without cracking. Flexibility is influenced by: 1) asphalt content 2) gradation Fatigue Resistance is the ability to resist repeated wheel loading, causing tensile strains and stresses. Factors influencing fatigue resistance are: 1. Air Voids 2. Asphalt Viscosity 3. Layer Thickness 4. Asphalt Content Skid Resistance is the ability to minimize skidding of vehicle tires, particularly under wet conditions. The following factors have an important impact on skid resistance: 1. Surface Roughness 2. Aggregate Texture 3. Asphalt Content Many of the above characteristics are related. An improvement of one value can have a detrimental effect on one of the other values. The design process, therefore, presents a trade-off to balance the different parameters among the various characteristics. The design concept of mixture design was formulated by Bruce Marshall. The U.S. Army Corps of Engineers, through extensive research and correlation studies, improved and added certain features to Marshall s original test procedure and developed mix design criteria. The Marshall method uses standard test specimens 2-1/2 inches high and 4 inches in diameter. A series of test specimens (3 per set), each containing the same aggregate blend but varying asphalt content, are prepared using specific procedures to heat, mix, and compact the asphalt-aggregate mixture. The two principle features of the method are 1) the stability-flow test, and 2) densityvoids analysis. Bulk specific gravity (Gmb) determination is essential for the accurate density/air voids analysis. The laboratory density becomes the standard by which the roadway density is measured. In Wisconsin, the DOT uses a percentage of maximum theoretical specific gravity (Gmm) as measured by AASHTO T209, commonly known as Rice Specific Gravity. The durability of dense-graded asphalt concrete mixes is related to air voids. The allowable percentage of air voids in laboratory compacted specimens is between 3% and 5%.

164 Appendix 1: Page 1-5 The voids in the mineral aggregate (VMA) are the air-void spaces that exist between the aggregate particles. The more VMA in the dry aggregate, the more space is available to accommodate the effective volume of asphalt (i.e., all of the asphalt except the portion lost by absorption into the aggregate) and the volume of air voids necessary in the mixture. Recycling Recycling provides an infinite source of material. Recycling in Wisconsin began by the late 1970s. Considerable maintenance costs have been saved because of recycling. Recycled material usually contains valuable aggregates and asphalt cement that can be reused. The milled and removed materials belong to the contractors who want to use this material in the most cost-effective way and that is in recycled HMA mixtures. However, the mixture containing RAP materials is required to meet the same specifications as a virgin mixture. In order to incorporate a RAP material in a mix design, the gradation of the RAP and the properties of the asphalt cement must be determined. Samples from the RAP stockpile are taken, and an extraction test is performed. The average of three extraction test results are usually used to characterize the RAP stockpile. The viscosity and penetration of the recovered asphalt are measured, also. Using the average aggregate gradation of the RAP stockpile, a blend with the available virgin aggregates is determined. The percent of RAP used is determined by the types of milled asphaltic pavement and the type of HMA facility so as to keep an efficient production while meeting opacity and emission requirements. Research by the author concluded that milled cold mixes will smoke more than milled hot mixes. The oxidation of asphalt is not uniform through the pavement. Depending on compaction and permeability, the upper portion of the pavement has oxidized more than the lower portion. The use of RAP requires modifications in the production facility. Typically, recycled material is introduced in the middle of the drum so that the RAP is introduced farther away from the flame. The percent RAP varies between 0-40 percent. It should be noted that in Wisconsin, if percent binder replacement exceeds requirements of standard spec , additional testing is needed. Viscosity blending charts are used to select a rejuvenating agent to mix with the RAP to restore the asphalt cement to its original viscosity. The grade of asphalt cement being added should be no more than two grades softer than the asphalt cement grade designed in the recycled mixture.

165 APPENDIX: QMP Award Nomination Form The Quality Management Program Award recognizes outstanding certified highway materials technicians who have displayed exceptional leadership roles in developing quality materials used in highway construction projects. These winners are chosen from contractors, consultants, and the Wisconsin Department of Transportation. It is this industry support and joint partnering that makes this program a success. Some of the qualities attributed to the award winners include HTCP certification, HTCP promotion, development of cost savings, development of time savings, quality improvement, being a team player and possessing a positive attitude. APPENDIX: Corrections APPENDIX: Course Evaluation

166 Quality Management Program Award Nomination Application This Outstanding Individual or Team is Nominated to Receive this Year s Quality Management Program Award Individual/Team: Address: City/State/Zip: Telephone: Employer: Work Address: City/State/Zip: Telephone: Fax : List individual or team nominated: Identify outstanding individual or team achievement(s) that exemplify this nomination for the Quality Management Program Award *Application submitted by: Do you wish to remain anonymous? (* Required for nomination) Yes No Date: Please fax (608) or send completed application before November 1 of each year to Highway Technician Certification Program, University of Wisconsin-Platteville, 049 Ottensman Hall, 1 University Plaza, Platteville, WI

167 OOPS! Found an error? Course Title: Please describe the error and the page or topic where you found it: We might have questions. How can we reach you? Name: Date: Phone: Note to Development Team: Send updates to or call , or mail to HTCP, 1 University Plaza, University of Wisconsin-Platteville, Platteville, WI THANK YOU!

168 HIGHWAY TECHNICIAN CERTIFICATION PROGRAM (HTCP) EVALUATION The HTCP would appreciate your thoughtful completion of all items on this evaluation. Your comments and constructive suggestions will be carefully studied and will serve as a valuable resource to improve our course presentations: Course: Date: 1. Overall rating of this program: Outstanding Above Average Average Below Average Unacceptable How prepared the course material made you for the examinations Quality and quantity of the course materials? How prepared the course has made you for the role you will be performing in your job Course registration process Please rate the relevancy of the technology used during the course. Please rate the responsiveness of the HTCP administrative staff. Please provide specific detail for ratings that are below average or unacceptable: Facilities/Lab Ratings: Outstanding Above Average Average Below Average Unacceptable Seating/size of the classroom Parking at the facility Size and layout of the lab Condition of the lab equipment Condition of the lab material. (Aggregate, concrete, asphalt, etc...) Please provide specific detail for ratings that are below average or unacceptable: