CERTIFIED TECHNICIAN HOT MIX ASPHALT I PRODUCTION TESTING (HMA-IPT)

Transcription

1 CERTIFIED TECHNICIAN HOT MIX ASPHALT I PRODUCTION TESTING (HMA-IPT) HIGHWAY TECHNICIAN CERTIFICATION PROGRAM University of Wisconsin-Platteville 049 Ottensman Hall 1 University Plaza Platteville, WI Office Phone; Fax:

2 Intro - 1 PREFACE The WisDOT Hot Mix Asphalt IPT Certification course manual was prepared and developed by the Highway Technician Certification Program (HTCP) staff, the HTCP instructors, and other contributors from the Wisconsin Department of Transportation (WisDOT) and the highway industry. The information contained in this course manual is intended to be used to train Hot Mix Asphalt I - Production Testing technicians in meeting the requirements of the WisDOT Quality Management Program. The intent of this manual is to illustrate the related AASHTO/ASTM test standards and also discuss the WisDOT Quality Management Program for Asphaltic Mixtures. It is the responsibility of the WisDOT Certified Technician in HMA-IPT to obtain and follow all current WisDOT asphaltic mixture specifications, policies and procedures. The WisDOT Hot Mix Asphalt IPT certification manual was developed in conjunction with these valuable resources: 1. Superpave Mix Design, Asphalt Institute, Superpave Series No. 2 (SP-2), 2. Hot Mix Asphalt Paving Handbook NAPA, AASHTO, US Army Corps of Engineers, FHWA, FAA, American Public Works Association, National Association of County Engineers 3. Hot Mix Asphalt for Seniors and Graduate Students, U.S. Department of Transportation, Federal Highway Administration, FHWA-IF The Aggregate Handbook, National Stone, Sand, and Gravel Association 5. Supervisors Safety Manual, ACKNOWLEDGEMENTS The following HTCP Hot Mix Asphalt Technical Manual committee members and class instructors have been very instrumental, along with many others, as contributors in developing the content of this course manual: John Jorgenson, Mathy Construction Steve Bloedow, Rock Road Co. Patrick Shuda, WisDOT NC Region (Wisconsin Rapids) Signe Reichelt, Behnke Materials Engineering Judie Ryan, WisDOT Bureau of Technical Services Jeff Merten, WisDOT SW Region, UW-Platteville Joe Kyle, American Asphalt Karl Runstrom, Northeast Asphalt Debbie Schwerman, WAPA WisDOT Technical Hot-Line, the Regions and Bureau of Technical Services Representatives: SW Matt.Smith@dot.wi.gov Madison Matt Smith SW Steven.Ames@dot.wi.gov LaCrosse Steve Ames SE James.Boggs@dot.wi.gov Waukesha James Boggs NE Brian.Jandrin@dot.wi.gov Green Bay Brian Jandrin NC Patrick.Shuda@dot.wi.gov WI Rapids Patrick Shuda NC Dean.Gritzmacher@dot.wi.gov Rhinelander Dean Gritzmacher 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 Jeff Anderson

3 Intro - 2 TABLE OF CONTENTS Course Overview Introduction and Syllabus TOPIC A TOPIC B TOPIC C TOPIC D TOPIC E TOPIC F TOPIC G TOPIC H TOPIC I TOPIC J TOPIC K TOPIC L TOPIC M History of WisDOT Quality Management Program How Asphalt Mixtures Behave HMA Aggregates Types of Asphalt Mixing Plants WisDOT HMA Pavement Types (and Mix Design Specifications) HMA Quality Management Program Summary Safety Random Sampling Procedure Sampling Asphaltic Mixtures from Truck Box Reduction of Asphaltic Mixtures to Testing Size AASHTO T Preparing and Determining the Density of Hot-Mix Asphalt (HMA) Specimens by Means of the Superpave Gyratory Compactor AASHTO T 166 Bulk Specific Gravity of Compacted SGC Bituminous Mixtures Using Saturated Surface-Dry AASHTO T 209 Maximum Specific Gravity of Bituminous Mixture TOPIC N WisDOT Extraction/Gradation Procedure CMM TOPIC O TOPIC P TOPIC Q TOPIC R Formulas, Calculations and Worksheets WisDOT Quality Control Charts WisDOT Quality Management Program Guide/CMM 8-36 QMP-HMA VACANT APPENDIX: 1 Laboratory Mix Design Reports, Additional Test Procedures 2 Standard Specification, Section 450 and 460, HTCP Laboratory Examination, QMP Award, Corrections, HTCP Course Evaluation

4 Intro - 3 MAJOR TABLES AND FIGURES REFERENCE LIST B-1 Asphalt Cement Time Temperature Dependency B-2 Visco-Elastic Behavior of Asphalt B-3 Example of PG Binder Designation B-4 Aggregate Stone Skeletons B-5 Stockpile Behavior of Cubical and Rounded Aggregate B-6 Rutting From Weak Subgrade B-7 Rutting from Weak Mixture B-8 Alligator (Fatigue) Cracking B-9 Low Temperature Cracking D-1 Batch Plant Components D-2 Batch Mix Facility Vibratory Screens and Hot Bin D-3 Drum Mix Facility Components D-4 Drum Plant Components E-1 Mix Design Applications E-2 Aggregate Gradation Master Range E-3 Table Mixture Requirements F-1 Verification Program G-1 Material Safety Data Sheet (MSDS) I-1 Single Dump Loading I-2 Multiple Dump Loading I-3 Sampling Plan for a Truck Box I-4 Example of Sample Labeling J-1 Initial Sample Reduction J-2 Sample Reduction for Testing K-1 Superpave Gyratory Compactor K-2 SGC Mold Configuration and Compaction Parameters

5 Intro - 4 Wisconsin Department of Transportation CERTIFIED TECHNICIAN HMA-IPT Syllabus Monday 8:00-8:30 Registration, Course Overview, and Definitions (Acronyms) 8:30-9:00 Introduction to Hot-Mix Asphalt 9:00-9:30 HMA Aggregates 9:30-10:30 Types of Asphalt Plants 10:30-11:45 WisDOT Specifications 11:45-12:45 Lunch Break 12:45-1:00 QC Overview 1:00-1:15 Safety 1:15-4:15 Laboratory Demonstration Reduction of Asphaltic Mixtures to Testing Size WisDOT 1560 HMA Solvent Extraction (including sieve analysis) AASHTO T 209 HMA Maximum Specific (G mm) o (Including Dryback Procedure) AASHTO T Preparing and Determining the Density of Hot-Mix Asphalt (HMA) Specimens by Means of the Superpave Gyratory Compactor AASHTO T 166 HMA Bulk Specific (G mb) Aggregate Specific Gravity Course and Fine (G sb) Aggregate Angularity (CAA & FAA) 4:15-5:00 Random Sampling Procedure Tuesday 8:00-8:45 Sampling Asphaltic Mixtures from Truck Box Reduction of Asphaltic Mixtures to Test Size 8:45-10:00 Recording Data to Worksheets Formulas and Calculations 10:00-11:30 Hands-On Asphaltic Mixture Laboratory 11:30-12:30 Lunch Break

6 Intro - 5 Tuesday (afternoon) 12:30-3:00 Hands-On Asphaltic Mixture Laboratory Testing 3:00-4:00 WisDOT HMA Field Control Charts 4:00-5:00 Set-UP Specified Control Charts and Plot Student Asphaltic Mixture Test Data Results Wednesday 8:00-9:00 Additional Testing Procedures (Appendix B) 9:00-12:00 Hands-On Asphaltic Mixture Laboratory Testing 12:00-1:00 Lunch Break 1:00-4:00 Hands-On Asphaltic Mixture Laboratory Testing 4:00-5:00 Plot Student Asphaltic Mixture Test Data on Control Charts Thursday 8:00-9:00 Appendix Items 9:00-11:30 Hands-On Asphaltic Mixture Laboratory Testing 11:30-12:30 Lunch Break 12:30-1:30 Plot Student Asphaltic Mixture Test Data on Control Charts 1:30-2:30 Review/Analyze/Troubleshoot Class Data and Wrap-Up 2:30-3:30 Review latest WisDOT Quality Management Program Guide/ Procedure Manual and Specifications 3:30-5:00 Course Review and Questions Friday 8:00-12:00 Written Examination (Four Hours Maximum) Course Evaluation ADJOURN

7 Intro - 6 Course Overview Introduction The Highway Technician Certification Program (HTCP) welcomes you to the Hot-Mix Asphalt IPT course. This course requires 36 hours of classroom attendance. The course content will cover types of asphalt plants, WisDOT QV/CA asphaltic quality management program procedures, WisDOT standard specifications, statistical quality control, and laboratory testing, such as: sampling, quartering, gyratory compaction, bulk specific gravity, rice maximum specific gravity, and WisDOT 1560 asphaltic solvent extraction. Course Prerequisites Student candidates must have successfully completed one construction season of field experience or equivalent education prior to enrollment and be certified as an Aggregate Technician I. A person may earn 3.6 continuing education units (CEU s) upon successful completion of this course. Certification Requirements The written examination will be limited to a maximum duration of four (4) hours. The written examination will be open book and open notes and will consist of short answer questions, multiple-choice questions, and essay problems. A student will be required to obtain a passing score of 70 percent to be certified as a Hot-Mix Asphalt IPT. 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. 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.

8 Intro - 7 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). Welcome The HTCP welcomes you to the Hot-Mix Asphalt Production Testing training/certification course. First of all, please make sure you have satisfied all Certified HMA Technician I course prerequisites before completing this course. Certification for Hot Mix Asphalt Production Testing will be granted only if you successfully complete this course and have satisfied all course prerequisites. Introduction of Course Participants 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 Certified Technician for Hot-Mix Asphalt Production Testing The duties and responsibilities of a Certified Hot-Mix Asphalt Production Tester (HMA- IPT) 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 Knowing the proper frequency of sampling and testing and being able to sample and test as required by specification

9 Intro - 8 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 to control production process by making troubleshooting adjustments which comply to 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 Acronyms Pertaining to Hot-Mix Asphalt AASHTO AC AMRL ASTM CA CAA ESAL FAA Gb Gmb Gmm Gsa Gsb Gse HMA JMF NAPA NCAT NCHRP NMAS Pb Pbe Pba PBR Ps QC QMP QV RAP SGC SHA SHRP SMA SSD TSR VFA VFB VMA VTM or VA WAPA WMA American Association of State Highway & Transportation Officials Asphalt Cement (Liquid Binder) AASHTO Materials Reference 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 National Asphalt Pavement Association National Center for Asphalt Technology National Cooperative Highway Research Program Nominal Maximum Aggregate Size % Binder Effective % Binder % Binder Absorption % Binder Replacement % Stone Quality Control Quality Management Program Quality Verification Recycled Asphalt Pavement Superpave (or SHRP) Gyratory Compactor State Highway Agency Strategic Highway Research Program Stone Matrix Asphalt Saturated Surface 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 Warm Mix Asphalt

10 TOPIC A: History of WisDOT Quality Management Program

11 TOPIC A: History of WisDOT Quality Management Program A-1 Below is a chronological outline of some of the recent history of HMA (hot-mix asphalt) in Wisconsin and the specifications that controlled design and production Rut Resistant HMA (RRHMA mixes) were brought about due to trouble in achieving VMA and in-place density. Crush counts lowered Natural sand restrictions increased to allow for greater use Density target changed to reflect a percent of Gmm Lower VMA requirements 1990 Letter Mixes (A,B,C,D,E) begin to identify mix types based on traffic loading A (Highest traffic volume): 5% air void target for lab design and adjusted to 4% in the field; VMA calc d using Gsb B (High traffic volume in urban sections): mixture adjusted to 3.5% air voids in the field; VMA calc d using Gsb C (Moderate traffic volume in rural state and CTH roadways): 4% air void target for lab designs; VMA calc d using Gse D (Lower traffic volume, usually single agg product): Sliding VMA scale based on aggregate top size and calc d using Gse E (Lease restricted mixes, temporary, and repair applications): Engineers suggested composition, no mix specifications Creation of RAP designs, primarily for the C mix applications, along with additional improvements and controls for the other letter mixes QMP program further developed and heading towards implementation (new HTCP classes). C and D mixes eliminated Contractor verification testing on state projects eliminated 1993 & 1994 Changes made to the specification to address low binder contents and segregation ESAL criteria used in developing HV - MV - LV mixtures Lessen the use of coarse gradations with thin film thickness and increase mixtures using small stones and thicker binder coating QMP requirement goals of 80% in 1993 and 100% by the end of 1994 Success in producing SMA test sections for future performance evaluation

12 TOPIC A: History of WisDOT Quality Management Program A through 1998 Recognition of the national SHRP conclusions and begin movement towards evaluating the use of the Superpave gyratory compactor in Wisconsin Development and implementation of Warranty for HMA specifications along with production of initial jobs under this specification Implementation of the SHRP Performance Graded binder specification (1997) 1999 through 2001 Superpave specifications modified and implemented as the mix design methodology of choice Superpave replaces HV mixes (little change to the materials requirements already in place) Special HTCP HMA courses updated and presented statewide to aid in education and training for the projected changes E-Mixes defined and related to 20 year life ESALs as suggested by AASHTO for the Superpave design system (in developing a national standard) WisDOT E-Mix specification to be implemented at a goal of 100% for 2001 (eliminating use of HV-MV-LV mixes) HMA quality control strategy is evolving from quality control/quality assurance (QC/QA) to contractor assurance/quality verification (CA/QV). The year 2004 marked the 10 th anniversary of 100% QMP state highway construction in Wisconsin 2015 Present HMA, Hot Mix Asphalt, begins to migrate to a name now more reflective of the product, Asphaltic Mixtures New LT - MT - HT mixes replace "E-mixes" (little change to the materials requirements) ESAL criteria used in developing LT - MT- HT mixtures MSCR specifications modified and implemented as the asphalt binder grading methodology of choice Air Void Regression used to increase asphalt content of mixtures Percent Within Limits used on select pilot projects for statistical analysis of QC & QV data to determine data acceptance and pay Dispute resolution shifts from interlaboratory test tolerance to test results (Va & VMA)

13 TOPIC B: How Asphalt Mixtures Behave

14 TOPIC B: How Asphalt Mixtures Behave B-1 Reference: Background of Superpave Asphalt Mixture Design and Analysis, National Asphalt Training Center, Pub. No. FHWA-SA , February 1995 ASPHALT MIXTURES Asphalt concrete (sometimes referred to as hot-mix asphalt or simply HMA ) is a paving material that consists of asphalt binder and mineral aggregate. Because HMA contains both asphalt binder and mineral aggregate, the behavior of the mixture is affected by the properties of the individual components and how they react with each other. The mix design system determines the correct proportion of asphalt binder and aggregate required to produce an asphaltic mixture with the properties and characteristics needed to withstand the effects of traffic and environment for many years. ASPHALT BINDER BEHAVIOR The asphalt binder, which can be asphalt cement or modified asphalt cement, acts as a binding agent to glue aggregate particles into a cohesive mass. Because it is impervious to water, the asphalt binder also functions to waterproof the mixture. When bound by the asphalt binder, mineral aggregate acts as a stone framework to give strength and toughness to the system. Almost every asphalt cement and mixture characterization test must be accompanied by a specified test temperature (Figure B-1). 140 o F 77 o F Figure B-1. Asphalt Cement Time Temperature Dependency Asphalt cement is sometimes referred to as a visco-elastic material because it simultaneously displays both viscous and elastic characteristics (Figure B-2). At high temperatures, asphalt cement acts almost entirely as a viscous fluid. In other words, when heated to a high temperature (e.g., > 212F / 100C), it displays the consistency of a lubricating fluid such as motor oil. At a very low temperature (e.g., < 32F / 0C), asphalt cement behaves most like an elastic solid. That is, it acts like a rubber band. When loaded, it stretches or compresses to a different shape. When unloaded, it easily returns to its original shape. At intermediate temperatures, which also happen to be

15 TOPIC B: How Asphalt Mixtures Behave B-2 those in which pavements are expected to function, the asphalt binder has characteristics of both a viscous fluid and elastic solid. elastic Stiffness Response to Load viscous elastic solid viscous fluid Temperature, C Figure B-2. Visco-Elastic Behavior of Asphalt The PG (performance grade) specifications help in selecting a binder grade (Figure B-3) that will limit the contribution of the binder to low temperature cracking, rutting, and fatigue cracking of the asphalt pavement within the range of climate and traffic loading for any particular project site. Modified asphalt binders are produced to alter and improve the properties of the asphalt to enhance the long-term performance of pavements. avg 7-day max pavement temp (147F) (- 8F) PG Lowest pavement design temp MINERAL AGGREGATE BEHAVIOR Figure B-3. Example of PG binder designation A wide variety of mineral aggregate has been used to produce HMA. Some materials are referred to as natural aggregate because they are simply mined from river or glacial deposits and are used without further processing to manufacture HMA. These are often called bank-run or pit-run materials. Processed aggregate can include natural aggregate that has been separated into distinct size fractions, washed, crushed, or otherwise treated to enhance certain performance characteristics of the finished HMA. However, in most cases processed aggregate is quarried and the main processing consists of crushing and sizing. An existing pavement can be removed and reprocessed to produce new HMA. Reclaimed (recycled) asphalt pavement or RAP is a growing and important source of aggregate for asphalt pavements.

16 TOPIC B: How Asphalt Mixtures Behave B-3 Regardless of source or processing method, aggregate is expected to provide a strong, stone skeleton to resist repeated load applications. Cubical, rough-textured aggregates provide more strength than rounded smooth-textured aggregates (Figure B-4). Even though a cubical piece and rounded piece of aggregate may possess the same inherent strength, cubical aggregate particles tend to lock together, resulting in a stronger mass of material. Rounded aggregate particles tend to slide by each other. Cubical Figure B-4. Aggregate Stone Skeletons Rounded Contrasting aggregate shear strength behavior can easily be observed in aggregate stockpiles (i.e.: crushed aggregates form steeper, more stable piles than rounded aggregates). Engineers refer to the slope on stockpiles as the angle of repose. The angle of repose of a crushed aggregate stockpile is greater than that of an uncrushed aggregate stockpile (Figure B-5). Figure B-5. Stockpile Behavior of Cubical and Rounded Aggregate

17 TOPIC B: How Asphalt Mixtures Behave B-4 To ensure a strong aggregate blend for HMA, engineers have typically specified aggregate properties that enhance the internal friction of the mixture. Normally, this is accomplished by specifying a certain percentage of crushed faces for the coarse portion of an aggregate blend and restricting use of rounded natural sands in the fine portion (FAA, Fine Aggregate Angularity). ASPHALT MIXTURE BEHAVIOR While the individual properties of HMA components are important, asphalt mixture behavior is best explained by considering asphalt cement and mineral aggregate acting as a system. One way to understand asphalt mixture behavior is to consider the primary asphalt pavement distress types that engineers try to avoid: permanent deformation, fatigue cracking, and low volume temperature cracking. Permanent Deformation (Rutting) Permanent deformation is the distress that is characterized by a surface cross section that is no longer in its proper position. It is called permanent deformation because it represents an accumulation of small amounts of deformation that occurs each time a load is applied. This deformation cannot be recovered. Wheel path rutting is the most common form of permanent deformation. While wheel path rutting can have many causes (e.g., underlying HMA weakened by moisture damage, abrasion, traffic densification), it has two principle causes. In one case, the rutting is caused by too much repeated stress being applied to the native soil (i.e., subgrade), subbase, or base below the asphalt layer (Figure B-6). original profile asphalt layer weak subgrade or underlying layer subgrade deformation Figure B-6. Rutting from Weak Subgrade The other principle type of rutting (and that which is of most concern here) results from accumulated deformation in the asphalt layers (Figure B-7).

18 TOPIC B: How Asphalt Mixtures Behave B-5 original profile weak asphalt layer Figure B-7. Rutting From Weak Mixture shear plane While the largest portion of the resistance to permanent deformation of the mixture is provided by the aggregate, the portion provided by the asphalt binder is very important. Binders which have low shear characteristics minimize cohesion. Thus the mixture begins to behave more like an unbound aggregate mass. Fatigue Cracking Like rutting, fatigue cracking is a distress type that most often occurs in wheel paths where repeated heavy loads are applied. An early sign of fatigue cracking is intermitt ent longitudinal wheel path cracks (i.e., in the direction of traffic). Fatigue cracking is a progressive type of distress because at some point, the initial cracks wil l join, whi ch in turn causes more cracks to form. An intermediate stage of fatigue cracking is sometimes called alligator cracking because the crack patterns resemble an alligator s skin (Figure B-8). In some extreme cases, the final stage of fatigue crackin g is a poth ole. Potholes form when several of the pieces become dislodged under the action of traffic. Figure B-8. Alligator (Fatigue) Cracking

19 TOPIC B: How Asphalt Mixtures Behave B-6 Low Temperature Cracking As its name indicates, low temperature cracking is a distress type that is caused by colder climate conditions rather than by applied traffic loads. Low temperature cracks form when an asphalt pavement layer shrinks in cold weather. It is characterized by transverse cracks (i.e., perpendicular to the direction of traffic) that occur at a surprisingly consistent spacing (Figure B-9). Low temperature cracks occur primarily from a single cycle or event of low temperature. Some engineers, however, also believe it s a fatigue phenomenon due to the cumulative effect of many cycles of cold weather. Figure B-9. Low Temperature Cracking The asphalt binder plays a central role in low temperature cracking and, in general, harder asphalt binders are more prone to low temperature cracking than soft asphalt binders.

20 TOPIC C: HMA Aggregates

21 TOPIC C: HMA Aggregates C-1 HMA Aggregates There are five general steps needed to prepare individual stockpiles of aggregates: Excavation, Transporting, Crushing, Sizing and Stockpiling, and Washing. Once stockpiles have been prepared, two or more stockpiles are typically blended together to produce a final gradation for a given construction application. Aggregate use for HMA also requires that standard source properties be measured for: Toughness (LA wear abrasion test to determine resistance to mechanical degradation) Soundness and/or Freeze-Thaw (to estimate resistance to weathering) Deleterious Materials (for contaminants such as clay lumps, wood, shale, chert) Gradation (sieve analysis to determine distribution of particle sizes) In addition, there are consensus properties that are measured as well: Aggregate Particle Shape (% crush for coarse and fine aggregates, CAA, and FAA) Flat & Elongated Particles (tendency for particle breakage) Sand Equivalency (clay content) Specific Gravity (G) All matter has mass and occupies space. Specific gravity can be defined as the weight of a body compared with the weight of an equal volume of water at 39 o F/4 o C (this is essentially the temperature at which water is densest). The densities of ordinary substances vary from the least dense, hydrogen gas (density of grams per cubic centimeter) to the element osmium, which at 22 grams per cubic centimeter is only slightly denser than gold or platinum. A material s specific gravity is a ratio of the mass to volume of an object to that of water at the same temperature (density of a substance divided by the density of water). A specific gravity value is expressed as how much greater the weight of the mineral is to an equal volume of water. Water has a specific gravity of If a mineral has a specific gravity of 2.725, it is times heavier than water. A ton of aggregate with a low specific gravity has a greater volume and will take up more space than a ton of aggregate with a higher specific gravity. Consequently, low specific gravity aggregate (high volume) requires more binder in order to coat the particles, to the same degree, as the same tonnage of higher specific gravity aggregates (low volume). Volumes of irregular-shaped objects are determined by the displacement of water and can be calculated by : volume of object = object wt. in air - object wt. in water. Mineral

22 TOPIC C: HMA Aggregates C-2 aggregate is porous and can absorb water and binder to a variable degree. That degree of absorption also varies with each aggregate source. There are three methods of measuring aggregate gravities to help take into account this variability: Apparent Specific Gravity (Gsa): volume excludes all pore space Effective Specific Gravity (Gse): volume includes partial pore space Bulk Specific Gravity (Gsb): total volume includes all pore space Gsa = smaller vol = larger gravity Gse = medium vol = medium gravity Gsb = larger vol = smaller gravity Specific Gravity Tests for Aggregates Two tests are needed in order to determine the specific gravity for aggregate components. Coarse aggregate (retained on the #4 / 4.75 mm sieve) Fine aggregate (passing the #4 / 4.75 mm sieve) Coarse Aggregate Specific Gravity (ASTM C127/AASHTO T85) Dry aggregate Soak in water for 24 hours Decant water Use pre-dampened towel to get SSD condition Determine mass of SSD aggregate in bucket Determine mass under water Dry to constant mass Determine oven dry mass

23 TOPIC C: HMA Aggregates C-3 Calculations G sb = A / (B - C) A = mass oven dry B = mass SSD C = mass under water G sa = A / (A - C) Water absorption capacity, % Absorption % = [(B - A) / A] * 100 Fine Aggregate Specific Gravity (ASTM C128 / AASHTO T 84) Dry aggregate Soak in water for 24 hours Spread out and dry to SSD Add 500 g of SSD aggregate to pycnometer of known volume o Pre-filled with some water Add more water and agitate until air bubble have been removed Fill to line and determine the mass of the pycnometer, aggregate and water Empty aggregate into pan and dry to constant mass Determine oven dry mass

24 TOPIC C: HMA Aggregates C-4 Fine Aggregate Specific Gravity Calculations G sb = A / (B + S - C) A = mass oven dry B = mass of pycnometer filled with water C = mass pycnometer, SSD aggregate and water S = mass SSD aggregate G sa = A / (B + A - C) Water absorption capacity, % Absorption % = [(S - A) / A] * 100 Sand Equivalence, SE (AASHTO T 176) Measured on the material passing the # 4 (4.75mm) The greater the SE value, the more sand and less clay there is Clay on the aggregate particles reduces binder adhesion to the stone Clay Content A = Clay reading B = Sand reading SE = B * 100 / A Coarse Aggregate Angularity, CAA Particle count conducted on R # 4 material and based on fractured faces One fractured face Two fractured faces

25 TOPIC C: HMA Aggregates C-5 Fine Aggregate Angularity, FAA (AASHTO T 304) Measured on the material between the # 8 (2.36mm) and the # 100 (.150mm) Based on air voids in a free falling loose sample Uses Method A (washed sample built back to a standard gradation) measured mass V - M / G sb V x 100% Flat and Elongated Particles (ASTM D 4791) Tested on the R # 4 (4.75mm) material Ratio of maximum to minimum dimension 5 1

26 TOPIC C: HMA Aggregates C-6 Voids in the Mineral Aggregate (VMA) VMA is defined as the volume of void space between the aggregate particles of a compacted mixture that includes the air voids and the volume of binder not absorbed into the aggregate (effective binder content, Pbe). In essence, it is a representation of the packing characteristics of the aggregate particles and determines the amount of space available for air voids and binder to fit in between the particles. Illustration of VMA in a Compacted Mix Specimen (Note: For simplification, the volume of absorbed asphalt is not shown.) G mb P s VMA 100 G sb Where Ps = (100 Pb) G VMA mb P b G sb

27 TOPIC D: Types of Asphalt Mixing Plants

28 TOPIC D: Types of Asphalt Mixing Plants D-1 The purpose of the hot-mix asphalt plant is to blend together different sized aggregates with asphalt binder to produce a high quality asphaltic mixture which can be placed and compacted into a durable asphaltic concrete pavement. Types of Asphalt Mixing Plants There are primarily two types of asphalt mixing plants used in Wisconsin: Batch Drum Batch Mix Facility Components Cold Feed Bins The production of Hot-Mix Asphalt (HMA) begins with aggregate stored in cold bed bins. (See Figure D-1 Batch Plant Components.) The cold feed bins are the primary feeders and main control of the asphalt plant. The cold feed bins must be calibrated before project start-up. A cold feed bin must be set up for each aggregate source, and each aggregate source percentage must be adjusted to meet the requirements on the asphaltic mix design report. The appropriate cold feed bin aggregate stockpiles and specified percentages make up the final production of the Job Mix Formula aggregate blend. Fourteen Major Parts: 1. Cold bins 9. Hot bins 2. Cold feed gate 10. Weigh box 3. Cold elevator 11. Mixing unit or pugmill 4. Dryer 12. Mineral filler storage 5. Dust collector 13. Hot asphalt cement storage 6. Exhaust stack 14. Asphalt weigh bucket 7. Hot elevator 8. Screening Unit Figure D-1. Batch Plant Components

29 TOPIC D: Types of Asphalt Mixing Plants D-2 An asphalt mixing facility has lots of moving conveyor belts and parts, so BE ALERT! SAFETY FIRST. From the cold feed bin, the aggregates are moved by a cold feed elevator to the dryer. The dryer has a burner, which provides the heat energy for evaporating the moisture in the aggregates and heats typically 285 o F / 140 o C to 300 o F / 149 o C. The dryer is equipped with longitudinal flights, which lift the aggregates and drop them through the hot burner gases. Once the aggregate material has been dried, the heated aggregate is discharged from the dryer and lifted to the top of an enclosed hot elevator. The hot dust gases are passed through a dust collect system to remove dust particles to be reintroduced back into the HMA by either an augering or flow metering system, as required. The hot elevator delivers the material to the tower unit, which will rescreen the aggregates with vibrating screens designed to separate the aggregates into different sized aggregate hot bins (see Figure D-2). Figure D-2. Batch Mix Facility Vibratory Screens and Hot Bins

30 TOPIC D: Types of Asphalt Mixing Plants D-3 After the material has been separated by the vibrating screens, the material is stored in hot bins. The computer control system then proportions the hot aggregates in the bins into the weigh hopper, which is mounted on a set of scales. Once the aggregates have been weighed, they are introduced into the pugmill, where the hot liquid asphalt binder is added. The hot asphalt binder has been weighed and stored in a weigh bucket and is sprayed onto the hot dry mixed aggregate. After the aggregates and asphalt cement have been mixed into the homogenous mixture, it is discharged directly into a truck or is transferred into a storage silo from which it may be loaded. Drum Mix Facility Components Cold Feed Bins Like the batch plant facility, the drum plant facility also uses cold feed bins as the primary feeder and control of the asphalt mixing facility. The secondary control in a drum mix facility is a conveyor belt scale, which weighs the aggregate before entering the drum. Troubleshooting cold feed bins is very similar to the batch plant facility. The basic parts of the drum mix plant: (See Figure D-3) Aggregate cold feed bins Conveyor and aggregate weighing systems Drum mixer (dryer) Dust collection system Hot mix conveyor Mix surge silo Control trailer Asphalt storage tank Figure D-3. Drum Mix Facility Components

31 TOPIC D: Types of Asphalt Mixing Plants D-4 As shown in Figure D-4, controlled gradations of aggregates are deposited in the cold feed bins (1) from which they are fed in exact proportions into a cold feed conveyor (2). An automatic aggregate weighing system (3) monitors the amount of aggregate flowing into the drum mixer (4). The weighing system is interlocked with the controls on the asphalt storage pump (5), which allows asphalt from the storage tank (6) and introduces it into the drum where asphalt and aggregate are thoroughly blended by the drums rotating action. A dust collector (7) captures excess dust escaping from the drum. From the drum, the hot-mix asphalt concrete is transported by hot-mix conveyor (8) to a surge silo (9) from which it is loaded into trucks and hauled to the paving site. All plant operations are monitored and controlled from instruments in the control van (10). Figure D-4. Drum Plant Components

32 TOPIC E: WisDOT HMA Pavement Types & Mix Design Specs

33 TOPIC E: WisDOT HMA Pavement Types & Mix Design Specs E-1 WisDOT HMA Pavement Types The type of HMA mix design will be specified as part of the project specifications. Selection of the appropriate HMA pavement type was developed on expected traffic loadings. The traffic loadings are defined in Equivalent Single Axle Loads (ESALs) the pavement is expected to carry in the design lane over a projected 20-year life. Name/ Type Design ESALS (millions) Compaction Parameters Nini Ndes Nmax Typical Roadway Applications LT < MT > 2 & < HT > Low traffic volumes, such as local roads, county roads, and city streets where truck traffic is prohibited or is at a very minimal level. Traffic on these roadways would be considered local in nature, not regional, intrastate or interstate. Special purpose roadways serving recreational sites or areas may also be applicable to this level. Many collector roads or access streets fall under this level as well. Medium trafficked streets and the majority of county roadways may be applicable to this level. Applications may include medium traffic two-lane, multilane, divided, and partially or completely controlled access roads. This level may also include some rural interstates. High traffic volumes found on many two-lane, multilane, divided roads. Among these are highly trafficked city streets, state routes, US highways, and US interstate system, both rural and urban in nature. Special applications such as truck-weighing stations or truck climbing lanes on two-lane roadways may also be applicable to this level. Table E-1. Mix Design Applications

34 TOPIC E: WisDOT HMA Pavement Types & Mix Design Specs E Aggregate Gradation Master Range Ensure that the aggregate blend, including RAP and mineral filler, conforms to the gradation requirements in table The values listed are design limits; production values may exceed those limits. 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 Table Aggregate Gradation Master Range and VMA Requirements 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] The HMA mix type for the WisDOT mix design will be specified as part of the project specifications. For example, a N o. 4 ( 12.5mm) HMA mixture is listed as part of the project specifications. The asphalt mix designer is responsible to design an HMA mixture, which satisfies both the No. 4 mix property requirements and the WisDOT aggregate gradation master requirements. The following table is an example of the WisDOT mixture requirements and represents the mix design limits for maximums and minimums. While the total of these properties is not monitored in the field on a regular basis, it should be noted that whenever adjustments are made to the original mix design JMF, these properties must be met as well.

35 TOPIC E: WisDOT HMA Pavement Types & Mix Design Specs E-3 Table MIXTURE REQUIREMENTS Mixture type LT MT HT SMA ESALs x 10 6 (20 yr design life) < <8 >8 > 5 mil 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 5821) (one face/2 face, % by count) Flat & Elongated (ASTM D4791) (max %, by weight) Fine Aggregate Angularity (AASHTO T304, method A, min) / 75 / / 90 [6] 100/90 5 (5:1 ratio) 5 (5:1 ratio) 5 (5:1 ratio) 20 (3:1 ratio) 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) % Gmm Nini <= 91.5 [1] <= 89.0 [1] <= 89.0 % Gmm Nmax <= 98.0 <= 98.0 <= (96.0) 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) (ASTM 4867) no antistripping additive with antistripping additive Draindown at Production Temperature (%) 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 MP3), 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%. [

36 TOPIC F: WisDOT HMA Quality Management Progam

37 TOPIC F: WisDOT HMA Quality Management Progam F-1 Quality Management Programs The quality of HMA can be defined in terms of the characteristics (e.g., asphalt content, air voids, density) required to achieve a specific level of excellence. Quality control, or process control, of HMA denotes mixing and placing the HMA ingredients (aggregates and asphalt) so that it is reasonable to expect the pavement to perform properly. Random sampling, as a piece of process control, is a procedure whereby every portion of mixture has an equal chance of being selected as a representative sample. Process control also provides a means of adequate checks during production to minimize the contractor s risk of having the mixture rejected. Quality control is described as contractor activities, efforts to meet specification requirements, and maintaining a given level of production with respect to acceptable levels of uniformity. Quality assurance is those activities providing a confidence level that the product will be or is, in fact, satisfactory. Acceptance testing is a check on the finished product to determine the degree to which the goals of contract/specification compliance and product quality have been attained. In addition, independent assurance is conducted to produce an unbiased/independent evaluation of the sampling and testing procedures used within the QMP. WisDOT Quality Management Program Requirements Personnel Requirements Laboratory Requirements Required Testing (and Calculated Properties) o Aggregate Gradation o Mixture Bulk Specific Gravity (Gmb) o Mixture Maximum Specific Gravity (Gmm) o Air Voids (Va) o VMA o Percent Binder Content o Tensile Strength Ratio (TSR) Random Sampling and Sampling Frequency Documentation o Records o Control Charts Control Limits Warning Bands Job Mix Formula Adjustments Corrective Action Assurance/Verification Testing

38 TOPIC F: WisDOT HMA Quality Management Program F-2 HMA Quality Management Program Summary Quality Management Program General Contractor shall provide and maintain a quality control (QC) program Mix design - JMF Process control inspection, sampling and testing Process adjustments related to the production and placement of HMA Department will provide product verification (and Independent Assurance as specified in ). Conduct verification testing of independent samples. Observe sampling and testing performed by the contractor. Monitor required production Direct the contractor to take additional samples at any time during production Contractor Testing (for a Contract of 5000 Tons of Mixture or Greater) Personnel Requirements Laboratory Requirements Required Testing at a specified Frequency Asphaltic content (AC) in percent Bulk specific gravity of the compacted mixture according to AASHTO T166. Maximum specific gravity according to AASHTO T 209. Air voids (Va) by calculation according to AASHTO T 269. Voids in the mineral aggregate (VMA) by calculation according to AASHTO R35. Tensile Strength Ratio (TSR) according to AASHTO T283 The above testing program shall be conducted for each design mixture at the specified frequency ( , paragraphs 5 and 6). Test Requirements for Contracts Other Than 5000 ton or Greater See Sections & 3 & 4 Documentation Records Control Charts Control Limits Job Mix Formula Adjustment

39 TOPIC F: WisDOT HMA Quality Management Program F-3 Corrective Action When running average values trend toward the warning limits, consider taking corrective action. Whenever the running average values exceed the warning limits, notify the engineer. If two consecutive running average values exceed the warning limits, stop production and make adjustments. Failure to stop production causes mixture to be considered unsatisfactory. Reduced payment will be applied. If the process adjustment improves the mixture running average to within the limits, no payment reduction is applied. If the adjustment does not improve the running average, the mixture will be considered unsatisfactory and a reduced payment will be applied Department Testing - Quality Verification Program General The engineer will conduct verification tests to determine the quality of the final product. Verification testing is intended to measure characteristics in predicting relative performance. Personnel Requirements Laboratory Requirements

40 TOPIC F: WisDOT HMA Quality Management Program F-4 Department Verification Testing Requirements Bulk specific gravity (Gmb) of the compacted mixture according to AASHTO T 166. Maximum specific gravity (Gmm) according to AASHTO T 209. Calculate Air Voids (Va) according to AASHTO T 269. Calculate VMA according to AASHTO R35 Testing is conducted for 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 Documentation Document daily: observations of QV sampling, review of mix adjustments, QC/CA test results Acceptable Verification Parameters Va; within a range of 2.0 to 4.3 percent. VMA; within 0.5 of the minimum requirement for the mix design NMAS If QV test results are outside the above acceptable parameters, the engineer investigates immediately (using dispute resolution procedures). If production continues, the engineer provides additional verification testing until such time that the material meets the acceptable parameters or as the engineer and contractor mutually agree. Dispute Resolution The QV-ret sample and the nearest available previous QC-ret sample will be referee tested by the department s Bureau of Technical Services AASHTO accredited laboratory and certified personnel. Notification of referee test results will be within 3 business days after receipt of the samples. Referee test results, mixture project data, any inspection of the completed pavement will be analyzed according to the department s QMP guide/procedure manual. Corrective Action All unacceptable material will be removed and replaced or paid at 50% Reduced payment for materials outside of the acceptable verification parameters for Va and VMA as identified above (if left in place) will be calculated according to the following: 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 )]

41 TOPIC F: WisDOT HMA Quality Management Program F-5 Footnotes: 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. Figure F-1. Verification Program

42 TOPIC G: Safety

43 TOPIC G: Safety G-1 Project Safety Precautions Safety is of prime importance while serving your occupational duty on the Wisconsin Department of Transportation (WisDOT) construction projects. Approximately 15% of all accidents are caused by unsafe mechanical or physical conditions. The other 85% of accidents result from absentmindedness, negligence, or ignorance of risk. No mysteries should surround an accident. All personnel involved with the project must be able to identify potentially dangerous situations and be prepared for preventive corrective action. Diagnosis of Any Accident There are five key elements in the diagnosis of any accident. 1. The agency or source of the accident; the item(s) directly related to the accident. 2. The type of accident; manner in which the person(s) were injured. 3. The unsafe condition; unsafe practice of person(s). 4. The unsafe act; unsafe practice of the person. 5. The body part and type of injury Each contributing element should be carefully analyzed and reported so a plan of corrective action can be developed and carried out to prevent future unnecessary accidents. While conducting your occupational duties on your project remember to keep in mind the following considerations: Know Your Safety Officer 1. Emergency Phone Numbers 2. Nearest Hospital Location Safety Equipment 1. First Aid Kit 2. Fire Extinguishers 3. Fireproof Gloves 4. Eye Protection 5. Ear Protection 6. Hardhats 7. Safety Vest 8. Proper Ventilation Equipment Operators Always keep good eye contact with operators when working close to heavy equipment.

44 TOPIC G: Safety G-2 Material Safety Data Sheet (MSDS) The Material Safety Data Sheet (MSDS) identifies the product, hazardous ingredients, physical data, fire and explosion data, health hazard data, emergency and first aid procedures, reactivity data, spill or leak procedures, special protection information, and special precautions associated with the use of the chemical. Generally, the MSDS should be located nearest to the area where the chemical is being used or stored. Also, a MSDS master copy should be kept on file at the main office of the company or agency. For example, refer to figure G-1. Material Safety Data Sheet (BIOACT High Flash). WisDOT uses BIOACT High Flash for breaking down petroleum distillates from the coated asphalt particles in a Hot-Mix Asphalt (HMA) mixture. Effects of High Temperatures As an asphalt technician you may be faced with working in a high temperature environment. Working in high temperatures causes your body to work harder (increasing your heart rate) to cool off your body. The capillaries in your skin dilate to bring more blood to the surface so both the rate of cooling and the temperature of the body are increased. You need to be aware of three high temperature conditions which may be life threatening: Heatstroke (also known as sunstroke) occurs when the body is unable to cool itself. Symptoms are hot dry skin, severe headache, visual disturbances, rapid temperature rise, and loss of consciousness. Heat stroke is the most serious of the high temperature conditions. The victim should be removed from the high temperature environment immediately and the body should be cooled as quickly as possible (being wrapped in cool wet sheets). Professional medical help should be obtained as soon as possible. Heat cramps may result from exposure to high temperatures for a relatively long period of time, typically accompanied by heavy exertion with excessive loss of salt and moisture from the body. Heat cramps cause cramping of the muscles of either the skeletal system or the intestines. Heat Exhaustion may result from physical exertion in a high temperature environment. The body cannot react enough to cool itself. Symptoms of heat exhaustion consist of relatively low temperature, paleness, weak pulse, dizziness, profuse sweating, and a cool mist to the skin. Heat cramps and exhaustion may be treated with the use of salt tablets. Generally, an adequate supply of salt is provided by a well-balanced diet.

45 TOPIC G: Safety G-3 Carrying and Lifting An asphalt technician will constantly be exposed to carrying and lifting as part of sampling and testing duties. The general rules to lifting and carrying include: 1. Never permit personnel to overexert themselves when lifting or carrying. Keep loads small by carrying or lifting smaller size samples. 2. Lift gradually, without jerking to minimize the effects of accelerated lifting. 3. Keep the load close to your body. 4. Lift without twisting your body. Hot-Mix Asphalt Safety Precautions The stored asphalt binder and the hot-mix asphalt on your project is generally heated to 290 F. Extreme caution and good judgment must be exercised while sampling and testing hot-mix asphalt materials. Mishandling of these materials may induce severe burns to workers leading to compensation and/or loss from occupational duties.

46 TOPIC G: Safety G-4 Figure G-1. Material Data Sheet (BIOACT High Flash) MATERIAL SAFETY DATA SHEET PETROFERMTM INC First Coast Highway Fernandina Beach, Florida (904) I. IDENTIFICATION Product Name: BIOACT High Flash Synonyms: CAS #: II. HAZARDOUS INGREDIENTS Weight OSHA PEL or Component Percent ACGIH TLV This product is non-hazardous as determined by the criteria set forth in appendices A and B of FR III. PHYSICAL DATA Boiling Point (760 mm Hg): 470 degrees 525 degrees F % Volatile (By Weight): Not determined. Specific Gravity (H2O = 1): 0.8 (25 degrees C) Vapor Pressure (20 degrees C): < 0.5 mm Hg Vapor Density (Air = 1): >1 Evaporation Rate (BUAC = 1): <1 Appearance and Odor: Water-white liquid, with a faint hydrocarbon odor. Solubility in Water: Emulsifiable. IV. FIRE AND EXPLOSION DATA Flash Point: 216 degrees F (ASTM D93-85, Pensky Martens Closed Cup Method). Flammable Limits (% By Volume in Air): 1.2% LEL.5.0%UEL Extinguishing Media: Water, alcohol foam, dry chemical, carbon dioxide. BIOACT is a registered trademark of Petroferm TM Inc. Special Fore Fighting Procedures: Selfcontained positive pressure breathing apparatus and protective clothing should be worn in fighting fires involving chemicals. Unusual Fire and Explosions Hazards: None known V. HEALTH HAZARD DATA SYMPTOMS/EFFECTS OF OVEREXPOSURE Inhalation: High vapor concentration may cause headaches and stupor. Ingestion: Low order of toxicity. Can cause irritation of the stomach and intestines resulting in nausea and vomiting. Skin: Repeated or prolonged contact with skin may cause irritation, reddening and dermatitis. Eyes: Contact with eyes will cause irritation. Listed Carcinogens: None. EMERGENCY AND FIRST AID PROCEDURES Inhalation: Remove to fresh air. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Ingestion: Do not induce vomiting; seek medical attention. Skin: Remove contaminated clothing. Thoroughly wash affected area with soap and water; use skin cream if irritation is severe. Call a physician if irritation persists. Eyes: Immediately flush eyes with water for 15 minutes. Call a physician if irritation persists.

47 TOPIC G: Safety G-5 Figure G-1. Material Data Sheet (BIOACT High Flash) BIOACT High Flash VI. REACTIVITY DATA Stability: BIOACT High Flash is stable Conditions to Avoid: Temperatures above 525 deg F Incompatibility: Strong oxidizing agents. Hazardous Decomposition Products: None, other than normal products of combustion. Hazardous Polymerization: Will not occur. Conditions to Avoid: None known. VII. SPILL OR LEAK PROCEDURES Steps to be Taken if Material is Released or Spilled: Absorb spill with inert material, then place in chemical waste container. For large spills, dike for later disposal. Observe government regulations. Waste Disposal Method: Waste treat or incinerate used material in compliance with all applicable government regulations. VIII. SPECIAL PROTECTION INFORMATION Respiratory: Not normally required. Use NIOSH/MSHA approved respirator if ventilation is not sufficient. Ventilation: Mechanical (general) ventilation should have an airflow of 55 CFM. Clothing/Gloves: Solvent resistant gloves are recommended for al use with all industrial chemicals. Eye Protection: Safety glasses/goggles are recommended for use with all industrial chemicals. Other Protective Equipment: Eyewash facilities. IX. SPECIAL PRECAUTIONS Precautions to be taken in Handling and Storing: Store in original container, preferable in a cool, ventilated, fire-resistant building. Avoid overheating or freezing. Other Precautions: Since empty containers may retain product residues (vapor, liquid, or solid) all labeled precautions must be observed. X. ADDITIONAL INFORMATION Regulatory Status: None of the components of BIOACT High Flash appear on any of the EPA s lists of toxic or hazardous substances, or on the SARA 313 toxic chemicals list (40CFR372.65). Because of the low vapor pressure of the product, high vapor concentrations are not normally encountered. None of the ingredients obtained in the product are listed in the Threshold Limit Value and Biological Exposure Indices complied by the American Conference of Governmental Industrial Hygienists. All the components of this product ate listed on the TSCA inventory. Date: 01/31/92 We believe that the information contained herein is current as of the date of this Material Safety Data Sheet. Since the use of this information and of these opinions and the conditions of use of the product are not within the control of PETROFERM in., it is the user s obligation to determine the conditions of safe use of the product.

48 TOPIC H : Random Sampling Procedure

49 TOPIC H : Random Sampling Procedure H-1 Random Sampling Sampling Hot Mix Asphalt At the beginning of each day, the contractor shall specify the anticipated tonnage to be produced. The frequency of sampling is then determined from the latest "Quality Management Program, Asphaltic Mixture specification. The anticipated tonnage shall be split into increments (600, 900, 1200, 1500 tons, and on ) and a sample obtained randomly from each increment. Refer to the latest copy of QMP specification to obtain the current required sampling frequencies. Example for Expected Production of 1900 Ton per Day: Number of Samples per day = 3 (per QMP specification in ) Increments of the following: Sample 1 - From 50 to 600 tons Sample 2 - From 601 to 1500 tons Sample 3 - From 1501 to 1900 tons The approximate location of each sample within the increments shall be determined by selecting random numbers from Table 1 of ASTM Method D-3665 according to the procedures in Sections 5.2 to 5.7 or by using a calculator that has a random number generator. The random numbers selected are used in determining when a sample is to be taken and shall be multiplied by the tonnage increments defined for the day. This number shall then be added to the final tonnage of the previous increment to yield the approximate total tonnage when the sample is to be taken. In allowing for plant start-up variability, this procedure calls for the first sample to be taken at 50 ton or greater per production day. Example 1: 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 400= This procedure is to be used for any number of samples per day. It is intended that the plant operator not be advised ahead of time of 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 prior to the mix sample being taken.

50 TOPIC H : Random Sampling Procedure H-2 RANDOM SAMPLING METHOD ASTM D 3665 Discussion and student problems will reference ASTM D 3665 method provided in the back of this section. STUDENT PROBLEM #1: 1) At the beginning of the day, the contractor told the QC person that they anticipated asphalt mix production of 2700 tons. Using the procedures in sections 5.2 to 5.7 and table 1 of ASTM Method D-3665, determine the following: a) Utilize the latest version of WisDOT section 460, Quality Management Program, Asphaltic Mixture specification to determine the number of random samples to be collected. b) Select the random numbers (obtain instructions from section 5.2 to 5.7, table 1, ASTM Method D-3665). Actual Sample No. 1 st Table No. 2 nd Table No.Line No. Column No. Random No. c) Determine the tonnage sampling plan. + Final Tonnage Tonnage Random Increment Ton Previous = Tonnage Sample No. Range Number X Random No. Increment Sampling

51 TOPIC H : Random Sampling Procedure H-3 RANDOM SAMPLING METHOD ASTM D 3665 STUDENT PROBLEM #2: 2. At the beginning of the day, the contractor told the QC person that they anticipated asphalt mix production of 1200 tonnage. Using the procedures in sections 5.2 to 5.7, and table 1, of ASTM Method D-3665 determine the following: a) Utilize the latest version of WisDOT section 460. Quality Management Program, Asphaltic Mixture specification to determine the number of random samples to be collected. b) Select the random numbers (obtain instructions from section 5.2 to 5.7, table 1, ASTM Method D-3665). Actual Sample No. 1 st Table No. 2 nd Table No.Line No. Column No. Random No. c) Determine the tonnage sampling plan. + Final Tonnage Tonnage Random Increment Ton Previous = Tonnage Sample No. Range Number X Random No. Increment Sampling

52 TOPIC H : Random Sampling Procedure H-4 RANDOM SAMPLING METHOD ASTM D 3665 STUDENT PROBLEM #3: 3. At the beginning of the day, the contractor told the QC person that they anticipated asphalt mix production of 3500 tons. Using the procedures in sections 5.2 to 5.7 and table 1 of ASTM Method D-3665, determine the following: a) Utilize the latest version of WisDOT section 460, Quality Management Program, Asphaltic Mixture specification to determine the number of random samples to be collected. b) Select the random numbers (obtain instructions from section 5.2 to 5.7, table 1, ASTM Method D-3665). Sample No. 1 st Table No. 2 nd Table No.Line No. Column No. Random No. c) Determine the tonnage sampling plan. + Final Tonnage Tonnage Random Increment Ton Previous = Tonnage Sample No. Range Number X Random No. Increment Sampling

53 TOPIC H : Random Sampling Procedure H-5 Random Sampling A typical random numbers chart follows on the next two pages. Here is how you use it to select a random number. A. The area under the bell curve, the normal distribution curve is segmented into 1000 equal pieces. Each of these areas is represented by a 3 digit decimal number. The first number is.001, the 23 rd number is.023, the 552 nd number is.552, etc., and the last number is B. The chart is printed on two pages. You may combine them on one sheet for convenience. It is a good practice to alternate pages. Use the page on the left, then the page on the right. For the next number, use the page on the right, then the page on the left. (You select these numbers by simply pointing at them with your fingers or a pencil, with your eyes shut.) C. Point at a number. Write down the first number you ve selected. Assume it is This is the first number in the chart. Point again. Use the second half of the chart on the right. Write down the second number you ve selected. Assume it is This is the last number in the chart. D. The first column (vertical) of numbers are the line numbers. There are 100 lines (rows). Use the first two digits of our first number, which are 2 and 7 or 27. This identifies row 27. Columns are numbered along the top. There are 10 columns. Note that the first column number is 0. Use the first digit of our second number, 0.119, which is 1. This identifies the second column. Using row 27 and column 1, our new random number is The key thought to remember when using this method for statistical sampling is It takes two numbers to get one number. E. There are nine exceptions to this procedure. Those exceptions are.001,.002,.003,.004,.005,.006,.007,.008, and.009. (The number is not in the chart). In the event that one of these numbers is selected in the pointing process, disregard that number and point at another. Student Question: What happens if you select in the pointing process? Answer: Use line 100.

54 TOPIC H : Random Sampling Procedure H-6 CHART OF RANDOM NUMBERS

55 TOPIC H : Random Sampling Procedure H CHART OF RANDOM NUMBERS Continued

56 TOPIC H : Random Sampling Procedure H-8 This material explains in detail the WisDOT method for statistical sampling. This doesn t replace the AASHTO Standards (i.e. T-2, etc.) or the ASTM standards (i.e. D-3665, etc.) that are referenced in those AASHTO Standards. You can get a copy of the AASHTO Standards at: American Association of State Highway & Transportation Officials 444 N. Capitol Street, N.W. Suite 249 Washington, DC (202)

57 TOPIC I: Sampling Asphaltic Mixtures from Truck Box Video: Hot Mix Asphalt-Truck Box Sampling

58 TOPIC I: Sampling Asphaltic Mixtures from Truck Box I-3 Checklist for HMA Sampling Observe sample to be random by asking for documentation Observe sample to be representative Insure complete identifying/label information: Paving Contractor Type of Asphalt Mixture QV/QV-ret WisDOT Mix Design ID # State Project ID # Percent Binder (%AC) Date Daily Tonnage Sampled Previous QC Sple # Current Gsb Full name of sampler (and contact phone #) Obtain a copy of mixture loadout ticket Minimum sample size < 12.5mm (1/2 ) 70 LB 19.0mm -25mm (3/4 1 ) 100 LB > 37.5mm (1-1/2 ) 160 LB Separate trucks for QC & QV samples Expedite samples to the Regional Lab (same/next day) as there are specification requirements for completion of testing. Checklist for HMA Sampling Observe sample to be random by asking for documentation Observe sample to be representative Insure complete identifying/label information: Paving Contractor Type of Asphalt Mixture QV/QV-ret WisDOT Mix Design ID # State Project ID # Percent Binder (%AC) Date Daily Tonnage Sampled Previous QC Sple # Current Gsb Full name of sampler (and contact phone #) Obtain a copy of mixture loadout ticket Minimum sample size < 12.5mm (1/2 ) 70 LB 19.0mm -25mm (3/4 1 ) 100 LB > 37.5mm (1-1/2 ) 160 LB Separate trucks for QC & QV samples Expedite samples to the Regional Lab (same/next day) as there are specification requirements for completion of testing.

59 TOPIC I: Sampling Asphaltic Mixtures from Truck Box I-2 Truck Loading Procedures Proper truck loading procedure may help alleviate problems with segregation (typically consisting of larger-sized aggregate particles rolling down the side of the pile) of Hot- Mix Asphalt (HMA) during load-out. When loading HMA into a truck, a single dump will produce segregation of HMA material all around the inside edges of the truck box (refer to figure I-1, Single Dump Loading). Figure I-1. Single Dump Loading (Produces segregation all around the inside edges of the truck box) Figure I-2. Multiple Dumps (Minimizes the segregated area within the truck box) Using multiple dumps reduces the surface area exposed to segregation, which, in turn, minimizes the segregation problem. The multiple dumps should be made as close as possible to the front and rear and the final dump should be placed in the center (refer to Figure I-2, Multiple Dumps). Sampling From the Truck Box Sampling from a truck box is the contractor s responsibility. This 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 obtained to prevent falls or burns. Sample Device. The shovel or other approved sampling device shall be of such size and configuration that each increment of a sample can be obtained in one attempt without spilling or roll off. In order to satisfy this requirement with a flat bottom shovel, it is necessary to attach two to four inch vertical sides to the shovel. The total sample size is required to be enough material to meet the testing and retained requirements as set by the QMP. For guidance on amount of material needed see Topic Q (Procedure , page 4).

60 TOPIC I: Sampling Asphaltic Mixtures from Truck Box I-3 When the last batch has been dumped into the truck box, 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 establish at least three incremental sample points about midway between the previously established point and the sides of the truck and equally spaced around the load (see sketch). At these sampling points, remove the upper two to three inches of mixture and then insert the sampling shovel or other approved device into the mixture to extract the sample increments and place increments in a sample container. The total sample for a 12.5 mm mix shall weigh at least 70 lb. X - Reference Point A - Sample Point B - Sample Point C - Sample Point Figure I-3. Sampling Plan for a Truck Box Sample Identification The contractor is responsible for procuring and splitting of samples. When the sample is an aggregate sample, it shall be split, placed in bags with plastic liners, and labeled as directed below. When a mixture sample is procured, it shall be quartered, placed in a bag and labeled as directed below. The label shall include: 1. Contractor 2. QC, QC-ret, QV, or QV-ret 3. State Project ID 4. Date 5. Sample Number 6. Type of Asphaltic Mixture 7. State Verification Mix Design Number 8. Percent Binder 9. Tonnage Sampled 10. Current Gsb HTCP QC-ret Prj. ID : /15/15 sple MT S % AC Current G sb : ,206 ton (day s) Figure I-4. Example of Sample Labeling

61 TOPIC J: Reduction of Asphaltic Mixtures to Testing Size

62 TOPIC J: Reduction of Asphaltic Mixtures to Testing Size J-1 WisDOT METHOD OF REDUCTION OF HMA SAMPLES TO TESTING SIZE The entire sample in the containers shall be mixed and quartered on a clean, smooth, metal surfaced table. The quartering process shall proceed as follows: Note: Accumulative/total tons, representing mix design production is 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 shall then proceed as follows: Step 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 the sketched example. For 12.5mm mixes start with at least a total of 70lbs (32kg) of HMA (see Figure 3). Superpave Sample 70lbs (32kg) Diagonal quarters, as indicated on the sketch, shall be combined to form the Retained sample (A + C) and the Test sample (B + D). The Retained sample is bagged, labeled and stored in a safe dry place. The Retained samples may be tested using the Rule of Retained. 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 (17 kg) of HMA material for testing, from Step 1, is to be further reduced for testing according to the following sketch (see Figure 4).

63 TOPIC J: Reduction of Asphaltic Mixtures to Testing Size J-2 Figure 5. MINIMUM TESTING SAMPLE SIZES NOTE: For QV samples: a Solvent Extraction Gradation (WisDOT CMM ) isn t required, so when quartering, the skewed areas may be smaller in size but all four pieces are combined for the Rice Test (Gmm). Use of Alternative Quartering Devices (Quartermaster) Use of other devices to assist in the quartering procedures may be used with approval of the Department. The Quartermaster is one such device and may be used for the initial two splits of the HMA.

64 TOPIC K: AASHTO T Preparing and Determining the Density of Hot-Mix Asphalt (HMA) Specimens by Means of the Superpave Gyratory Compactor

65 TOPIC K: AASHTO T 312 K-1 Reference: Background of Superpave Asphalt Mixture Design and Analysis, National Asphalt Training Center, Demonstration Project 101, Publication No. FHWA-SA SUPERPAVE GYRATORY COMPACTION TEST EQUIPMENT The SGC (Figure K-1) is a mechanical device comprised of the following system of components: reaction frame, rotating base, and motor loading system, loading ram, and pressure gauge height measuring and recordation system mold and base plate Compaction Key Components of Gyratory Compactor 13 Figure K-1. Superpave Gyratory Compactor The reaction frame provides a structure against which the loading ram can push when compacting specimens. The base of the SGC rotates and is affixed to the loading frame. It supports the mold while compaction occurs at an angle of 1.25 degrees, which is the compaction angle of the SGC. The electric motor drives the rotating base at a constant speed of 30 revolutions per minute.

66 TOPIC K: AASHTO T 312 K-2 Specimen height measurement is an important function of the SGC. By knowing the mass of material placed in the mold, the diameter of the mold, and the specimen height, an estimate of specimen density can be made at any time throughout the compaction process. The SGC uses a mold (Figure K-2) with an inside diameter of 150 mm and a nominal height of 250 mm. A base plate fits in the bottom of the mold to afford specimen confinement during compaction. Figure K-2. SGC Mold Configuration and Compaction Parameters

67 TOPIC K: AASHTO T 312 K-3 Significance and Use The compaction procedure for the Superpave method of mix design compacts asphaltic mixture into SGC specimens approx 5.75 (150mm) in diameter and approx 4.5 (115mm) in height. The SGC specimens are used to determine percent air voids, density and tensile strength ratio. 2 Place HMA sample in an oven for a 1 hour maximum at o F in flat pan(s) to bring mix to compaction temperature 4 Load HMA mix (generally grams for WisDOT mixes) into the compaction mold(s) in 1 charge. Rotate the pan around the mold to avoid segregation Laboratory Equipment 1. Superpave Gyratory Compactor 2. Metal Spatula 3. Thermometer 4. 2 Compaction molds 5. 4 Specimen Protection Discs 6. Metal Trowel 7. 2 pans If the mix sample, after quartering, is still within the acceptable temperature range, for compaction, then further stabilizing of temperature in an oven is not required. 3 Place a specimen protection disc into the bottom of the pre-heated compaction mold(s). 5 With a spatula, lightly level the mix to be flat on the top. Place another specimen protection disc on top of the mixture.

68 TOPIC K: AASHTO T 312 K-4 6 Ensure the mixture is at a compaction temperature of F (132C 137 o C). 8 Perform compaction with a Superpave Gyratory Compactor and apply the specified number of gyrations on each SGC specimen (using Ndes from the mix design). removal of the bottom paper. 10 After extruding, cool all SGC specimens laying flat for a minimum of 1 hour before conducting the bulk specific gravity test procedure. Refer to the section for AASHTO T166 (Bulk Specific Gravity of Compacted Bituminous Paving Mixtures Using Saturated Surface-Dry Specimens). 7 Load the gyratory compactor with the specimen (according to the manufacturer s instructions) 9 Extrude specimen and remove protection discs from each side of compacted SGC specimen and let cool. 11 Label each specimen Note: when handling very fine or tender mixtures it s recommended to extrude the compacted sample only partially and cool for up to 10 minutes before completely extruding and

69 TOPIC L: AASHTO T 166 (WisDOT Overview) Bulk Specific Gravity of Compacted SGC Bituminous Mixtures Using Saturated Surface-Dry

70 TOPIC L: AASHTO T 166 (WisDOT Overview) L-1 Significance and Use This test method covers the determination of bulk specific gravity (Gmb) and density of specimens of compacted bituminous mixtures. 2 Weigh each SGC specimen in air and record. (designate this weight as A). 5 Surface dry the specimen by blotting quickly with a damp towel and then weigh in air, and record (designated this weight as B). Laboratory Equipment 1. Water Bath 2. Water temp Control Device 3. Electronic Balance/Scale 4. Under Water Weigh Device 5. Timer 6. Damp Towel 3 Water bath temperature is to be maintained at 77F + 2F (24C-26C). 6 Perform Gmb calculation and calculate to three decimal places. (0.001) 1 Allow newly compacted SGC specimens to cool for a period of one hour not to exceed two hours. Gmb = Example: A A B - C 4 Immerse the specimens in 77F + 2F (24C-26C) water bath for 3 to 5 minutes. Weigh in water, and record (designate this weight as C). G mb G mb G mb B - C

71

72 TOPIC M: AASHTO T 209 (WisDOT Overview)

73 TOPIC M: AASHTO T 209 (WisDOT Overview) M-1 The maximum specific gravity (G mm) and density of bituminous paving mixtures is an important property whose values are influenced by the composition of the mixtures in terms of types and amounts of aggregates and bituminous materials. 1. It is used to calculate values for percent air voids in compacted bituminous paving mixtures. 2. It provides target values for the in-place compaction of paving mixtures. 3. It is essential when calculating the amount of binder absorbed by the internal porosity of the individual aggregate particles in a bituminous paving mixture. 1 Obtain the appropriate sample of asphaltic mixture. 2 After the G mm has been subjected to oven heating (mirror the G mb sample), thoroughly break up mixture so that particles of the fine aggregate portion are not larger than ¼ inch. A fan may be used to aid in the cooling process. 4 Add enough potable water, of 77o F + 2F (24C- 26C) to completely cover the mix sample by approximately 1 inch (25mm). 5 With spatula stir to help release any trapped air. Laboratory Equipment 1. Vacuum Pycnometer 2. Manometer 3. Vacuum Pump 4. Thermometer 5. Water Bath 6. Protective Gloves 7. Weigh Pan 8. Large Flat Pan 9. Potable Water 10. Cooling Fan 3 Add asphaltic mixture to the dry precalibrated pycnometer flask. Weigh and record. 6 Ensure a small piece of fine wire mesh covers the exit hose of the pycnometer vacuum cover to minimize the possibility of fine material loss.

74 TOPIC M: AASHTO T 209 (WisDOT Overview) M-2 7 Apply vacuum for minutes once the internal pycnometer has reached less than 30 mm Hg. of vacuum pressure (maintain in a range ± 2.25, 25.5 to 30.0). 9 At the completion of minutes vacuum period, use caution to release the internal vacuum pressure slowly (mercury filled manomaters could explode through the end of the glass tube if done too quickly). 11 Allow the sample (temperature and pressure) to stabilize for a period of 10 minutes (+ 1 minute) 8 Agitate pycnometer flask approximately every 2 minutes during the vacuum period. 10 Add potable water of 77F + 2F (24C 26C) to fill the pycnometer flask by floating the container in the water bath, being careful not to introduce additional air bubbles. 12 Place the lid on pycnometer flask and carefully, slowly with even pressure, press lid so that excess water spurts out of the calibration port (this ensures the same amount of water is being compared to the water measured for the calibrated volume of the pycnometer).

75 TOPIC M: AASHTO T 209 (WisDOT Overview) M-3 13 Remove the pycnometer from the water bath and dry completely the outside perimeter of lid and pycnometer. Optional (provided the room temperature is being maintained between 70F - 80F ( 21C 27C) 12a. Next, place lid on pycnometer so that excess water spurts out of the calibration port. 10a. Add potable water of 77F + 2F (24C 26C) to fill the pycnometer flask to 1/16 inch below the pycnometer flask surface edge, being careful not to introduce additional air bubbles. 14 Weigh and record pycnometer flask, lid, water and asphaltic mixture. Example of Rice Test equipment setup: 11a. Let pycnometer flask, lid and HMA mixture stand for minute to stabilize temperature and pressure. 12a. Next, place lid on pycnometer so that excess water spurts out of the calibration port.

76 TOPIC M: AASHTO T 209 (WisDOT Overview) M-4 15 Prepare asphaltic mixture for dry back process. A dry back test is required to determine if the pores of the aggregates have been properly sealed with a bituminous film. The dry back procedure will measure any additional water, in grams, that has penetrated the seal of the bituminous film. The dry back is used to correct the Gmm value. Weigh dry pan. 16 Drain water from the Gmm asphaltic mixture by decanting over 75 m (No 200) sieve, cloth or paper towel. 17 Spread sample in pan to dry. A fan may be used to expedite the drying process. 18 Determine when the asphaltic mixture and pan are visibly free of standing water and begin weighing the asphaltic mixture and pan at 15 minute intervals. When the asphaltic mixture and pan reaches a constant weight of within 0.5 gram of the previous 15 minute weighing, record this as the final weight of pan and final saturated surface dry (SSD) weight on your worksheet. Perform Gmm calculation (three decimal places to the right)

77 TOPIC N: WisDOT Extraction/Gradation Procedure, CMM

78 TOPIC N: WisDOT Extraction/Gradation Procedure, CMM N-1 HMA Extraction Gradation Using Solvent WISCONSIN DEPARTMENT OF TRANSPORTATION DIVISION OF TRANSPORTATION SYSTEM DEVELOPMENT BUREAU OF TECHNICAL SERVICES MATERIALS MANAGEMENT SECTION 1. Scope Field Solvent Extraction Method for Determining the Aggregate Gradation of Asphaltic Mixture Samples WisDOT Test Method for Solvent Extraction Gradation December 14, 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. 2. Apparatus 2.1 Pans (approximately 12 by 8 by 3 deep), bowls (approximately 10 quarts) or pails (approximately 10 quarts). 2.2 Balance shall be an electronic type with a 5-20 kg capacity and sensitivity to 0.1 g. 2.3 Solvent shall be a biodegradable, high flash and nontoxic asphalt extractant. 3. Procedure 3.1 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 shall be heated until dry, approximately 30 to 60 minutes. 3.2 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.

79 TOPIC N: WisDOT Extraction/Gradation Procedure, CMM N 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 stockpile samples). Note: Excessive soaking time in the solvent will require more water washes and will cause more smoking during the drying operation. 3.4 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(es) will aid in extracting the binder from the aggregate when using RAP mixtures.

80 TOPIC N: WisDOT Extraction/Gradation Procedure, CMM N 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. 3.6 Conduct a sieve analysis on the extracted aggregate (AASHTO Test Method T 27) in order to identify the gradation of the sample. 4. Calculation 4.1 Calculate the total dry weight of the aggregate as follows: Where: Wagg = Wmix * ( 1 (AC% / 100) ) Wagg = Total dry weight of the aggregate Wmix = Total dry weight of the mixture determined in section 3.1 AC% = Percent asphalt determined in section Calculate the gradation as required using the dry weight of aggregate (Wagg) as determined above. 5. Report 5.1 The results of the sieve analysis should be reported to the nearest 0.1 percent. NOTE: Field experience has demonstrated that High Flash solvent performs better 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!

81 TOPIC O: Formulas, Calculations, and Worksheets

82 TOPIC O: Formulas, Calculations, and Worksheets O-1 DESCRIPTION OF TERMS Term Identifier Description Air Voids Va or VTM total volume of the small air pockets between coated aggregate particles; expressed as a percentage of the bulk volume of the compacted paving mixture Voids in the Mineral Aggregate Effective Asphalt Content Voids Filled with Asphalt Aggregate Bulk Specific Gravity Aggregate Effective Specific Gravity Asphalt Binder Specific Gravity VMA P be VFA G sb G se Gb the volume of inter-granular void space between the aggregate particles of a compacted paving mixture that includes the air voids and effective asphalt content; expressed as a percentage of the total volume of the compacted paving mixture the total asphalt content of the paving mixture less the portion of asphalt binder that is absorbed by the aggregate particles; expressed as a percentage of the total weight of the compacted paving mixture the portion of the VMA that contains asphalt binder; expressed as a percentage of the total volume of mix or VMA the ratio of the mass in air of a unit volume of aggregate, including permeable and impermeable voids, to the mass of an equal volume of water, both at the same temperature the ratio of the mass in air of a unit volume of aggregate, excluding voids permeable to asphalt, to the mass of an equal volume of water, both at the same temperature the ratio of the mass in air of a given volume of asphalt binder to the mass of an equal volume of water, both at the same temperature

83 TOPIC O: Formulas, Calculations, and Worksheets O-2 Mixture Bulk Specific Gravity Theoretical Maximum Specific Gravity of the Mix Volume of Absorbed Asphalt G mb G mm V ba the ratio of the mass in air of a given volume of compacted HMA to the mass of an equal volume of water, both at the same temperature the ratio of the mass of a given volume of HMA with no air voids to the mass of an equal volume of water, both at the same temperature. the volume of asphalt binder that has been absorbed into the pores of the aggregate STANDARD CONVENTIONS The following conventions are used to abbreviate binder, aggregate, and mixture characteristics: Specific Gravity (G): Gxy x - b = binder s = aggregate (i.e., stone) m = mixture y - b = bulk e = effective a = apparent m = maximum theoretical Mass (P) or Volume (V) Concentration: Pxy or Vxy x - b = binder s = aggregate (i.e., stone) a = air y - e - effective a = absorbed (Note: standard conventions do not apply to Vba and Pfa)

84 TOPIC O: Formulas, Calculations, and Worksheets O-3 FORMULAS AND CALCULATIONS: BULK SPECIFIC GRAVITY (Gmb) DETERMINATION G mb A B C Determine the Bulk Specific Gravity, Gmb, for the following (calculate to three decimal places): Given: Weight in Air (A) = g Weight in Water (C) = g SSD Weight (B) = g MAXIMUM SPECIFIC GRAVITY (Gmm) DETERMINATION G mm A A B C Determine the Maximum Specific Gravity, Gmm, for the following (calculate to three decimal places: Given: Dry Weight of Mix (A) = g Weight of Pot + Water (B) = g Weight of Pot + Mix + Water (C) = g

85 TOPIC O: Formulas, Calculations, and Worksheets O-4 CALCULATING AIR VOIDS The air void (%Va) determination is a relationship between maximum specific gravity (Gmm) and bulk specific gravity (Gmb). Calculate to one decimal place. Va,% G mm - G mb 100 G mm Calculate the percent Va (using the average Gmb given). Calculation should be expressed to one decimal place. Given: Gmb = Gmm = VOIDS IN MINERAL AGGREGATE, VMA, CALCULATIONS VMA is calculated using the aggregate bulk specific gravity, Gsb, from the contractor mix design, the asphalt content (Pb determined from the amount of asphalt being added at the time of sample), and the average SGC specimen bulk specific gravity, Gmb, as follows (calculate to one decimal place): Note: Pb = Ps (or % stone) VMA, % = 100 [ G mb X (100 P b ) ] or VMA = 100 [ G mb X P s ] G sb G sb Determine the Voids in Mineral Aggregate, VMA, with the following data. (Calculate VMA to one decimal place.) Given: Pb = 5.4 Gmb = Gsb = 2.742

86 TOPIC O: Formulas, Calculations, and Worksheets O-5 When a hot mix plant aggregate bin percentage is changed by five percent or more from the job mix formula, calculate the Gsb as follows: G sb = P 1 + P P n P 1 G + P 2 1 G + + P n 2 G n * W here P is the component blend % and G is the component Gsb Note: If the Gsb=s of the interchange materials are essentially the same, do not recompute. 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 to three decimal places. G se = (100 P b) ( 100 P b G mm G ) b Determine the Gse (Aggregate Effective Specific Gravity) of the mix design with the following (calculate to three decimal places): Given: Pb = 5.40 (tank stick) Gb = Gmm = (daily avg)

87 TOPIC O: Formulas, Calculations, and Worksheets O-6 DETERMINATION OF PERCENT OF ASPHALT CONTENT (Pb) P b = 100 X ( G b ) X (G se G mm ) G mm (G se G b ) Determine the Percent Asphalt Content (Pb) of the mix design with the following (calculate to one decimal place): Given: Gse = Gb = Gmm = (single test result) ADDITIONAL USEFUL FORMULAS Observe the effective specific gravity and the bulk specific gravity of the aggregate blend have been calculated, an estimate of the absorbed asphalt content (Pba) can be made using the following equation: P ba 100 G se G sb G sb G G b se Understanding that the absorbed asphalt content is expressed as a percentage of the mass of the aggregate, an estimate of the effective asphalt content (Pbe) of the HMA mixture can be made using the following equation: P be P b P ba 100 P s ANSWERS TO PROBLEMS Page O-3: Bulk Specific Gravity = 2.422; Maximum Specific Gravity = Page O-4: Percent Air Voids = 4.9; Voids in Mineral Aggregate = 16.4 Page O-5: Aggregate Effective Specific Gravity = Page O-6: Percent Asphalt Content = 5.4

88 TOPIC O: Formulas, Calculations, and Worksheets O-7 DESIGN # Sple ID # MixType : Gmb : compacted Bulk SpGr A / (B - C) Gsb (design) Gse (current) Date : Spl ID Dry Wt (A) Wt Smrgd (C) SSD Wt (B) Vol (B - C) Gmb 1 2 Compaction Effort : Average Gmm (Rice / Max SpGr) (Pb) total % binder in Mix 1 Flask / Pot ID # 2 Wt. of Flask + Mix 3 Wt. of Flask A Dry Wt. of Mix (2-3) A1 * SSD Wt. of Mix (4-5) D Wt. of Flask + Water E Wt. of Flask + Water + Mix F Gmm = A / (A+D-E) G Gmm (w/ssd) = A / (A1+D-E) 4 Final SSD wt of Pan + mix 5 Tare Wt. of Pan Gmm corrected for reheat Solvent Extraction Gradation : wt Mix * [ 1 - (Pb / 100)] = wt Agg Dryback (SSD) of Mix Dryback PAN ID # Minutes/Time 0:00 = Pan + mix * Using Dryback Corr Factor A1 = [(A*CF) / 100] + A % Va wt of Mix sample = wt Agg = (Gmm-Gmb) / Gmm*100 Sieve Sizes Cumm wt retained % Retained % Passing 25.0mm - 1 " /4" / / # # 8 % VMA [Gmb * (100 - Pb) / Gsb] # # # # # 200 % VFB (VMA - Va) / VMA * 100

89 TOPIC O: Formulas, Calculations, and Worksheets O-8 DESIGN # Sple ID # MixType : Gmb : compacted Bulk SpGr A / (B - C) Gsb (design) Gse (current) Date : Spl ID Dry Wt (A) Wt Smrgd (C) SSD Wt (B) Vol (B - C) Gmb Compaction Effort : Ndes = 75 Average Gmm (Rice / Max SpGr) (Pb) total % binder in Mix Flask / Pot ID # 21 2 Wt. of Flask + Mix Wt. of Flask A Dry Wt. of Mix (2-3) A1 * SSD Wt. of Mix (4-5) D Wt. of Flask + Water E Wt. of Flask + Water + Mix F Gmm = A / (A+D-E) G Gmm (w/ssd) = A / (A1+D-E) 4 Final SSD wt of Pan + mix 5 Tare Wt. of Pan Gmm corrected for reheat Solvent Extraction Gradation : wt Mix * [ 1 - (Pb / 100)] = wt Agg wt of Mix sample = wt Agg = Sieve Sizes Cumm wt retained % Retained % Passing 25.0mm - 1 " /4" / / # # # # # # # Dryback (SSD) of Mix Dryback PAN ID # Minutes/Time 0:00 = Pan + mix * Using Dryback Corr Factor A1 = [(A*CF) / 100] + A % Va (Gmm-Gmb) / Gmm*100 % VMA [Gmb * (100 - Pb) / Gsb] % VFB (VMA - Va) / VMA * 100

90 TOPIC O: Formulas, Calculations, and Worksheets O-9 DESIGN # Sple ID # MixType : Gmb : compacted Bulk SpGr A / (B - C) Gsb (design) Gse (current) Date : Spl ID Dry Wt (A) Wt Smrgd (C) SSD Wt (B) Vol (B - C) Gmb Compaction Effort : Ndes = 75 Average Gmm (Rice / Max SpGr) (Pb) total % binder in Mix Flask / Pot ID # 21 2 Wt. of Flask + Mix Wt. of Flask A Dry Wt. of Mix (2-3) A1 * SSD Wt. of Mix (4-5) D Wt. of Flask + Water E Wt. of Flask + Water + Mix F Gmm = A / (A+D-E) G Gmm (w/ssd) = A / (A1+D-E) 4 Final SSD wt of Pan + mix 5 Tare Wt. of Pan Gmm corrected for reheat Solvent Extraction Gradation : wt Mix * [ 1 - (Pb / 100)] = wt Agg wt of Mix sample = wt Agg = Sieve Sizes Cumm wt retained % Retained % Passing 25.0mm - 1 " /4" / / # # # # # # # Dryback (SSD) of Mix Dryback PAN ID # Minutes/Time 0:00 = Pan + mix * Using Dryback Corr Factor A1 = [(A*CF) / 100] + A % Va (Gmm-Gmb) / Gmm* % VMA [Gmb * (100 - Pb) / Gsb] 14.4 % VFB (VMA - Va) / VMA *

91

92 TOPIC P: WISDOT QUALITY CONTROL CHARTS

93 TOPIC P: WisDOT Quality Control Charts P-1 Control Charts Control charts provide a means for the contractor to identify when corrections should be made during production. The plotted data, particularly those for the average values, show trends as they develop. As trends move toward the limits, the contractor will have advance warning to assess action options and correct the production process. Control charts do not identify the source of the process variability. When a contractor investigates an undesirable trend, it may be determined that something (an assignable cause) happened in the process that has caused the trend. An example may be when a hole develops in a sieve and increases in size with use. Ideally, the inferior sieve would be found and replaced with a suitable sieve before the process advanced to a point where test results would be out of specification. This latter condition may result in stoppage of the manufacturing operations and/or possible penalties to the contractor. Benefits of Control Charts Early Detection of Trouble Decrease Variability Establish Process Capability Reduce Price Adjustment Costs Decrease Inspection Frequency Basis for Altering Spec Limits Permanent Record of Quality Provide a Basis for Acceptance Instill Quality Awareness In reality, control charts, when properly used, should provide an early detection system for identifying potential trouble spots for the contractor. Obviously, the contractor should review control charts regularly to stay on top of the production process. Depending on the severity of the data or data trend being produced, the contractor may react by taking immediate corrective action or determine to monitor the process a while longer before deciding on a course of action.

94 TOPIC P: WisDOT Quality Control Charts P-2 Corrective Action When the moving average trend for any of the control chart values is towards the warning limits, the contractor should consider corrective action. Corrective action must always be documented. The corrective action undertaken may be to increase the sampling and testing rate, to inspect laboratory equipment, to inspect plant equipment, to initiate adjustments in controlling the process, and/or to change materials or quantities and combinations of these actions. In addition to documenting corrective actions, resulting effects of the corrective actions should be recorded. When the moving average for any of the control chart values exceeds the warning limits, the contractor will notify the engineer. This should be done immediately, as soon as the value is determined. If a second consecutive moving average value for a particular property exceeds the warning limits, the contractor will stop production and make adjustments. Quality through production control is the responsibility of the contractor. Any disregard by the contractor to attend to controlling the process or for making no effort to take corrective action, when warranted, is grounds for material to be considered unsatisfactory. Should the contractor encounter a situation, in which he/she is unable to get the process under control in a timely manner, consideration should be given to various alternatives. If the material is obviously defective or inferior, the contractor should not use the material on the project. When any moving average value is trending towards the warning limits, the contractor shall consider corrective action. When any single moving average value exceeds the warning limits (enters the warning band), the contractor shall notify the engineer. When a second consecutive moving average value exceeds the warning limits (in the warning band), the contractor will stop production and make adjustments. Note: Failure by the contractor to control the production process can be grounds for the material to be considered unsatisfactory.

95 TOPIC P: WisDOT Quality Control Charts P-3 The following control chart legend is used: Upper Warning Limit - UWL Upper Warning Band - UWB JMF Target Band TB (area between Warning Limits) Lower Warning Limit - LWL Lower Warning Band LWB JMF Limit control limits (defines unacceptable property parameters) QC Individual Test Result QC Moving Average of 4 QC Non Random Test. QC-ret Individual Test Result... X AIR VOID Chart UWB JMF Limit UWL TB LWL LWB Test # JMF Limit 12

96 TOPIC P: WisDOT Quality Control Charts P-4 CONTROL CHART EXAMPLES AIR VOIDS UWB JMF Limit UWL TB X LWB Limit Test # LWL JMF EXAMPLE A: At test point 5 a trend of the running average toward the warning band has developed and the contractor should consider corrective action. At point 6 the contractor notifies the engineer that the first moving average is in the warning band. At point 7 the contractor notifies the engineer that the second consecutive moving average is in the warning band. At this point the contractor must stop production and make adjustments. Production may only be restarted after notifying the engineer of the adjustments made. In this example the moving average after four additional individual tests (point 11) is back within the target band.

97 TOPIC P: WisDOT Quality Control Charts P-5 Student Problem: WisDOT Quality Control Charts 1) Utilize the test data shown below, for the No. 8 (2.36 mm) sieve, calculate the moving (running) average of four for each test battery of data. The JMF target for the No. 8 (2.36 mm) sieve is 50.0%. Date Test 2.36 mm Ave (4) 8/01/ /02/ /03/ /06/

98 TOPIC P: WisDOT Quality Control Charts P-6 2) Set-up the attached control chart for the No. 8 (2.36 mm) sieve in accordance with the latest copy of the quality management program specifications: a) Establish and plot the upper and lower control limits (JMF Limits) b) Establish and plot the upper and lower warning limits. c) Plot and connect the individual contractor QC data points. d) Plot and connect the moving (running) average data e) Identify and explain the corrective action responsibility at test # 3-2 and 3-3. f) Identify and explain the corrective action responsibility at test # 4-1. g) Identify and explain the corrective action responsibility at test # 4-2.

99 TOPIC P: WisDOT Quality Control Charts P-7 Student Problem: ANSWER 1) Utilize the test data shown below, for the No. 8 (2.36 mm) sieve, calculate the moving (running) average of four for each test battery of data. The JMF target for the No. 8 (2.36 mm) sieve is 50.0%. Date Test 2.36 mm Ave (4) 8/01/ /02/ /03/ /06/

100 TOPIC P: WisDOT Quality Control Charts P-8

101 Appendix 1: SMA Draindown (AASHTO T 305) Tensile Strength Ratio, TSR (AASHTO T 283) Laboratory Mix Design Reports Laboratory Exam

102 Standard Method of Test for Determination of Draindown Characteristics in Uncompacted Asphalt Mixtures AASHTO Designation: T SCOPE 1.1. This test method covers the determination of the amount of draindown material in an uncompacted asphalt mixture sample when the sample is held at elevated temperatures comparable to those encountered during the production, storage, transport, and placement of the mixture. The test is particularly applicable to mixtures such as porous asphalt (open-graded friction course) and Stone Matrix Asphalt (SMA) The values stated in SI units are to be regarded as the standard This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standards: R 47, Reducing Samples of Hot Mix Asphalt (HMA) to Testing Size T 245, Resistance to Plastic Flow of Asphalt Mixtures Using Marshall Apparatus T 255, Total Evaporable Moisture Content of Aggregate by Drying 2.2. ASTM Standard: E11, Standard Specification for Woven Wire Test Sieve Cloth and Test Sieves 3. TERMINOLOGY 3.1. Definitions: draindown material For the purpose of this test method, draindown material is considered to be that portion of material that separates itself from the sample as a whole and is deposited outside the wire basket during the test. The draindown material may be composed of either asphalt binder or a combination of asphalt binder and fine aggregate draindown The process by which draindown material separates itself from the sample as a whole. TS-2c T AASHTO 2016 by the American Association of State Highway and Transportation Officials.

103 4. SUMMARY OF METHOD 4.1. A sample of the asphalt mixture to be tested is prepared in the laboratory or obtained from field production. The sample is placed in a wire basket, which is positioned on a plate or other suitable container of known mass. The sample, basket, and plate or container are placed in a forced-draft oven for 1 h at a preselected temperature. At the end of 1 h, the basket containing the sample is removed from the oven, along with the plate or container and the mass of the plate or container is determined. The amount of draindown material is then calculated. 5. SIGNIFICANCE AND USE 5.1. This test method can be used to determine whether the amount of draindown material measured for a given asphalt mixture is within acceptable levels. The test provides an evaluation of the draindown potential of an asphalt mixture during mixture design or during field production. This test is primarily used for mixtures with high coarse aggregate content such as porous asphalt (open-graded friction course) and SMA. 6. APPARATUS 6.1. Forced-Draft Oven Capable of maintaining the temperature in a range from 120 to 175 C (250 to 350 F). The oven should maintain the set temperature to within ±2 C (±3.6 F) Plates Or other suitable containers of appropriate size. The plates or containers used should be of appropriate durability to withstand the oven temperatures. Cake pans or pie tins are examples of suitable types of containers Standard Basket Meeting the dimensions shown in Figure 1. The basket shall be constructed using standard 6.3-mm (0.25-in.) sieve cloth as specified in ASTM E Balance Accurate to 0.1 g Other apparatus Spatulas, trowels, bowls, and mixer as needed. 7. SAMPLE PREPARATION 7.1. Laboratory-Prepared Samples: Number of Samples For each mixture tested, the draindown characteristics should be determined at two different temperatures. The two temperatures should be the anticipated plant production temperature, as well as 15 C (27 F) above that temperature (Note 1). For each temperature, duplicate samples should be tested. Thus for one asphalt mixture, a minimum of four samples will be tested. Note 1 When using the test as part of the mixture design procedure, the test should be performed at two temperatures in order to determine the potential effect that plant temperature variation may have on the mixture during production. When the test is used in the field during production, it should be necessary to perform the test at the plant production temperature only Dry the aggregate to a constant mass in accordance with T 255, and sieve it into the appropriate size fractions as indicated in T Determine the anticipated plant production temperature or select a mixing temperature in accordance with T 245. TS-2c T AASHTO 2016 by the American Association of State Highway and Transportation Officials.

104 Place into separate pans for each test sample the amount of each size fraction required to produce completed mixture samples having a mass of 1200 ± 200 g. The aggregate fractions shall be combined such that the resulting aggregate blend has the same gradation as the job mix formula. Place the aggregate samples in an oven and heat them to a temperature not to exceed the mixing temperature established in Section by more than approximately 28 C (50 F) Heat the asphalt binder to the temperature established in Section Figure 1 Wire Basket Assembly TS-2c T AASHTO 2016 by the American Association of State Highway and Transportation Officials.

105 Place the heated aggregate in the mixing bowl. Add any stabilizers (Note 2) and thoroughly mix the dry components. Form a crater in the aggregate blend and add the required amount of asphalt binder. The amount of asphalt binder shall be such that the final sample has the same asphalt content as the job mix formula. At this point, the temperature of the aggregate and asphalt binder shall be within the limits of the mixing temperature established in Section Using a spatula (if mixing by hand) or a mixer, mix the aggregate (and stabilizer, if any) and asphalt binder quickly until the aggregate is thoroughly coated. Note 2 Some types of stabilizers, such as fibers or some polymers, must be added directly to the aggregate prior to mixing with the asphalt binder. Other types of stabilizers must be added directly to the asphalt binder prior to blending with the aggregate Plant-Produced Samples: Number of Samples For plant-produced samples, duplicate samples should be tested at the plant production temperature Samples may be obtained during plant production by sampling the mixture at any appropriate location, such as the trucks prior to the mixture leaving the plant. Samples obtained during actual production should be reduced to the proper test sample size by R 47. Note 3 Caution should be exercised when sampling from surge or storage bins because draindown may already have taken place. 8. PROCEDURE 8.1. Transfer the hot laboratory-produced or plant-produced uncompacted mixture sample to a tared wire basket as described in Section 6.3. Place the entire sample in the wire basket. Do not consolidate or otherwise disturb the sample after transferring it to the basket. Determine the mass of the sample to the nearest 0.1 g. Care should be exercised to ensure that the sample does not cool more than 25 C (77 F) below the test temperature. (See Section 8.2.) 8.2. Determine and record the mass of a plate or other suitable container to the nearest 0.1 g. Place the basket on the plate or container and place the assembly into the oven at the temperature as determined in Section or for 60 ± 5 min. If the sample has cooled more than 25 C (77 F) below the test temperature, the test should be conducted for 70 ± 5 min After the sample has been in the oven for the time specified in Section 8.2, remove the basket and plate or container from the oven. Determine and record the mass of the plate or container plus draindown material to the nearest 0.1 g. 9. CALCULATIONS 9.1. Calculate the percent of mixture that drained by subtracting the initial plate or container mass from the final plate or container mass and dividing this value by the initial total sample mass. Multiply the result by 100 to obtain a percentage. M f Mi 100 = percent of mixture that drained or percent draindown M t TS-2c T AASHTO 2016 by the American Association of State Highway and Transportation Officials.

106 where: M f M i M t = final plate or container mass; = initial plate or container mass; and = initial total sample mass. 10. REPORT Report the average percent draindown (average percent of mixture that drained) at each of the test temperatures. 11. KEYWORDS Asphalt mixture; draindown; fiber; open-graded friction course; porous asphalt; SMA; stabilizer. 1 Minor editorial revisions have been made at the discretion of the authors responsible for standards on Asphalt Aggregate Mixtures (technical section 2c). TS-2c T AASHTO 2016 by the American Association of State Highway and Transportation Officials.

107 TSR AASHTO T 283 Significance and use This test method can be used to test asphalt concrete mixtures in conjunction with mixture design testing to determine the potential for moisture damage, to determine whether or not an antistripping additive is effective, and to determine what dosage of an additive is needed to maximize the effectiveness. This test method can also be used to test mixtures produced in plants to determine the effectiveness of additives under the conditions imposed in the field. Laboratory Equipment 1. Vacuum Chamber 2. Vacuum Pump 3. Manometer 4. Scale or Balance 5. Water Baths (3) 6.Mechanical or Hydraulic Testing Machine 7. Loading Strips 2 Obtain the appropriate asphaltic mixture sample from the field sample(s) or prepare a laboratory batch which will produce 6 specimens. 3 After batching, oven cure ( F). 4 Compact the specimens with the predetermined count from the TSR Trials Worksheet. 5 Cool all of the specimens in the mold(s) to the hand touch, then extrude with hydraulic jack apparatus. 1 Gravity by AASHTO T 166 and Maximum Specific Gravity by AASHTO T 209. Calculate air voids and plot no. of verses percent air voids. Connect data points and determine specified gyration count, which is between the range of 6% - 8% air voids. 6 Sort the specimens into two equal subsets so the average air voids of the two subsets are approximately equal. Store one at room temperature. Wet Conditioned Dry SubSet

108 7 Partially saturate each specimen of the wet subset by applying a vacuum. The goal is to partially saturate each specimen to a saturation point between 55% and 80% volume of water. If the applied partial vacuum does not satisfy reach at least the 55% saturation point additional vacuum may be applied. Percent saturated condition is calculated as per worksheet. Any specimen saturated more than 80% is over saturated and must be discarded from the subset. 9 Adjust the temperature of the moistureconditioned subset by soaking in a water bath for 2 hours at degrees Fahrenheit ( degree Celsius. 10 Adjust the temperature of the dry subset by soaking in a water bath. At degrees Fahrenheit ( degrees Celsius. Apply the load at 2 in./min until maximum load is reached and record maximum load. 12 Continue loading until the specimen fractures. Break the specimen open and visually estimate and record the approximate degree of moisture damage, if any. Inspect all surfaces, including the failed faces, for evidence of racked or broken aggregate, that may influence test results and record all observations. 8 Moisture condition the partially saturated specimens by soaking in distilled water at degrees Fahrenheit ( degrees Celsius) for 24 hours. 11 Determine the tensile strength at degrees Fahrenheit ( degree Celsius of both subsets. Place a specimen into the loading apparatus and position the loading strips so that they are parallel and centered on the test specimen. 13 Calculate the individual specimen strength values and subset averages to compare by ratio (avg wet strength divided by the avg dry strength) and determine the TSR value (per worksheet).

109 Effect of Moisture on Asphalt Concrete (AASHTO T 283) Asphalt Cement Content (P b ): % (A) Diameter, in (B) Height, in (C) Mass in air, g (D) Mass SSD, g (E) Mass under water, g (F) Volume, cm 3, = (D E) (G) Bulk specific gravity (H) Max. specific gravity (I) Air voids, % = 100 (1 G/H) (J) Vol of voids, cm 3 = (I x F/100) Initial Vacuum Saturation Conditioning (K) Mass SSD (L) Vol of absorbed water, cm 3 = K C (M) % Saturation 100 (L/J) (O) Failure load, lb (P) Tensile strength, psi = (2 x O ) / (π A B) Average tensile strength ratio (P 4 + P 5 + P 6) / (P 1 + P 2 + P 3) * 100 Unconditioned Samples Conditioned Samples Calculations

110 TESTING SAWED OR CORED PAVEMENT SAMPLES Determine pavement bulk specific gravity using AASHTO T166 (ASTM D-2726) for specimens that contain moisture. Immerse the specimens in F water bath for 3-5 minutes and weigh in water, designate this weight as C. Surface dry the specimens by blotting quickly with damp towel and then weigh in air (include any water that may drain from voids in specimens), designating this weight as B. Oven-Dry the specimen back to a constant weight, in an oven set to 230F + 9F (105C - 115C), designating this weight as A. Calculate the Gmb to three decimal places, Pavement Gmb = A B-C Note: When using pavement cores to evaluate the percentage of compaction effort (inplace density) you can divide the core Gmb by the Gmm, then multiply by 100 (Gmb/Gmm* 100) to get the percent compaction. If the moisture has not been completely dried out of the core, then the resultant percent compaction may be artificially high (air voids will appear to be a bit lower than actually are).

111 Core ID Thickness A1 apparent dry wt C Submerged wt B SSD wt A oven-dry wt D Volume ( B - C ) Gmb ( A/D ) Apparent Gmb ( A1/D ) Pan Tare wt Dryback min 0 min 30 min 60 min 90 min Final Dryback - Pan wt = A Core ID Thickness A1 apparent dry wt C Submerged wt B SSD wt A oven-dry wt D Volume ( B - C ) Gmb ( A/D ) Apparent Gmb ( A1/D ) Pan Tare wt Dryback min 0 min 30 min 60 min 90 min Final Dryback - Pan wt = A

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125 Student Date HIGHWAY TECHNICIAN CERTIFICATION PROGRAM THE UNIVERSITY OF WISCONSIN-PLATTEVILLE TECHNICIAN CERTIFICATION PROGRAM HMA TECHNICIAN IPT QUALIFYING LABORATORY EXAM Area of Qualification Pass/Fail Instructor A. Sampling B. Bulk Specific Gravity C. Maximum Specific Gravity D. Sawed or Cored Pavement E. WisDOT Extraction/Gradation Comments:

126 EXPLANATION The practical laboratory examination for the Hot-Mix Asphalt Technician IPT consists of a combination of oral and practical (hands-on) presentations to the laboratory instructor. The instructor will use the attached checklist to verify fine and key points in any given test. In the practical examination, the student will be given an actual sample. The student will do the hands-on tests on his/her own under the observation and questioning of the instructor and present the results to the instructor. Successful Completion Successful completion of examination includes the satisfactory completion of the following: 1. The instructor will engage the student in oral discussion on any of the attached areas with which the student must be thoroughly familiar. The student should satisfactorily explain any part of the hands-on training included in Asphalt Technician IPT, including purpose of test and how the data is used. 2. The student must demonstrate acceptable skill in performing the laboratory procedures presented in Asphalt Technician IPT. Parts where the student shows lack of full comprehension must be repeated. HMA TECHNICIAN-IPT Practical Laboratory Examination Oral Examination Instructions: 1. The instructor may choose one or more of the following sub-categories to test the student s understanding of the laboratory procedures. 2. If the instructor is in doubt of the student s understanding, the number of testing categories may be increased.

127 A. Sampling COMPLETED A.1 Responsibility for sampling A.2 Location for sampling A.3 Sampling procedure A.4 Sample reduction procedure B. Bulk Specific Gravity (Gmb) Procedure COMPLETED B.1 B.2 Specimen molds and equipment pre-heated in an oven at 300F. Each specimen (enough material to attain a final specimen height of 115 mm ±5 mm) placed in a flat pan and placed for a maximum of one hour at F to bring mix standard compaction temperature. B.3 Place a paper disc in the bottom of heated specimen. B.4 Place full contents of flat pan into the mold in one lift action (additional funnels or scoop chutes may be used in order to accomplish this). B.5 Ensure a compaction temperature of about 275 ± 5F. B.6 Perform compaction. How many gyrations are required? Where do you find that information? B.7 After compaction is completed, extrude the specimen. B.8 Remove protective paper discs and label briq. B.9 Cool briq by fan on a flat surface for one hour not to exceed 2 hours. Why is this important? B.10 Water temperature for Gmb should be 77 ±2F (25C). Why this temperature? B.11 Sample should be submerged for three to five minutes in water before weighing.

128 B.12 SSD weight in air is determined after blotting specimen quickly with a damp towel. B.13 Compute individual specimen Gmb. Determine average Gmb of four specimens. Check for specified uniformity with ±0.015 standard. Explain what to do if they don t. C. Maximum Specific Gravity COMPLETED C.1 Cure sample in 300F oven to 30 minutes to one hour. C.2 Sample broken up and let cool to room temperature, care being taken not to fracture the mineral particles or having remaining conglomerates of fine aggregate greater than ¼ inch. C.3 Place sample in pre-calibrated container C.4 Weigh container and sample. C.5 Add water at 77 ±2F (25C) to cover sample. Wetting agent may be added. C.6 Apply required partial vacuum for 15 ±2 minutes. Agitate container every two minutes to assist in air removal. C.7 After completion of vacuum, fill container with controlled temperature water. Place lid, adjust water level, and weigh. C.8 Drain water from sample, decanting water through a towel or a #200 sieve held over top of container to prevent loss of fine particles. C.9 Back dry the sample. While drying, intermittently stir the sample. Break conglomerations by hand.

129 C.10 Weigh at 15 minute intervals until loss in weight is less than 0.5 g for a given interval. Sample is then considered SSD. D. Sawed or Cored Pavement COMPLETED D.1 Obtaining pavement samples is contractor s responsibility. D.2 Explain normal condition of field samples as received. Describe core preparation before testing. D.3 Testing procedure for Gmb: Immerse in water at 77 F (25 C) for three to five minutes and determine submerged weight. Surface dry the sample by blotting with damp cloth and determine weight. Oven dry the sample at 230 ± 9 F and determine weight. D.4 Compute Gmb of cores as required by contract. E. Extraction Using Solvent WisDOT CMM COMPLETED E.1 Obtain a representative sample of asphaltic mixture according to the latest copy of the department s procedure manual. E.2 Dry sample for 10 to 20 minutes in oven at 275 ±20F (RAP stockpile samples shall be heated until dry, approximately 30 to 60 minutes). E.3 Weigh sample to the nearest 0.1 gram. E.4 Determine the percent asphalt being added to the mixture at the time the sample was obtained from the settings of the asphalt plant for produced mixtures (RAP stockpile samples, use the asphalt content shown for the RAP on the mix design). E.5 Place mixture in the pan, pail, or bowl and cover with solvent (agitate the sample gently with spatula).

130 E.6 Soak plant produced mixtures 15 to 30 minutes and RAP stockpile samples for 30 to 60 minutes. Note: Excess soaking time in the solvent will require more water washed and cause more smoke during the drying period. E.7 Decant the solvent, pouring over a No. 8 sieve nested over a No. 200 sieve. Dispose of solvent by an approved method. Continue rinsing with water until the wash water is clear. Material retained on either of the two sieves shall be washed back into the sample. E.8 Decant off any excess water (care should be taken to avoid the loss of particles for the AASHTO Test Method T 27). E.9 Dry the sample to a constant weight in an oven or on a hot plate (avoid excessive temperature in the drying process). E.10 Conduct a gradation test on the aggregate according to the procedures of AASHTO Test Method T 27.

131 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

132 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

133 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!