1. Division 31 Section "Earthwork" for aggregate subbase and base courses.

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1 SECTION ASPHALT PAVING PART 1- GENERAL 1.1 RELATED DOCUMENTS Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 1 Specification Sections, apply to this Section. 1.2 SUMMARY This Section includes the following: 1. Hot-mix asphalt paving. 2. Hot-mix asphalt patching. 3. Hot-mix asphalt paving overlay. 4. Cold milling of existing asphalt pavement. B. Related Sections include the following: 1. Division 31 Section "Earthwork" for aggregate subbase and base courses. 1.3 DEFINITIONS Hot-Mix Asphalt Paving Terminology: Refer to ASTM D 8 for definitions of terms. B. MoDOT: Missouri Department of Transportation. 1.4 SYSTEM DESCRIPTION Provide hot-mix asphalt paving according to materials, workmanship, and other applicable requirements of standard specifications of MoDOT. 1. Standard Specification: Missouri Standard Specifications for Highway Construction, latest edition. 2. Measurement and payment provisions and safety program submittals included in standard specifications do not apply to this Section. 1.5 SUBMITTALS Product Data: For each type of product indicated. Include technical data and tested physical and performance properties. B. Job-Mix Designs: For each job mix proposed for the Work. c. Qualification Data: For manufacturer. D. Material Test Reports: For each paving material. E. Material Certificates: For each paving material, signed by manufacturers. 1.6 QUALITY ASSURANCE Manufacturer Qualifications: A qualified manufacturer. SECTION ASPHALT PAVING -1-

2 1. Manufacturer shall be a paving-mix manufacturer registered with and approved by the Missouri Department of Transportation. B. Testing Agency Qualifications: Qualified according to ASTM D 3666 for testing indicated, as documented according to ASTM E 548. C. Regulatory Requirements: Comply with Missouri Standard Specifications for Highway Construction for asphalt paving work. D. Asphalt-Paving Publication: Comply with AI MS-22, "Construction of Hot Mix Asphalt Pavements," unless more stringent requirements are indicated. 1.7 DELIVERY, STORAGE, AND HANDLING Deliver pavement-marking materials to Project site in original packages with seals unbroken and bearing manufacturer's labels containing brand name and type of material, date of manufacture, and directions for storage. B. Store pavement-marking materials in a clean, dry, protected location within temperature range required by manufacturer. Protect stored materials from direct sunlight. 1.8 PROJECT CONDITIONS Environmental Limitations: Do not apply asphalt materials if subgrade is wet or excessively damp or if the following conditions are not met: 1. Tack Coats: Minimum surface temperature of 60 deg F. 2. Asphalt Base Course: Minimum surface temperature of 40 deg F and rising at time of placement. 3. Asphalt Surface Course: Minimum surface temperature of 60 deg F at time of placement. PART 2 -PRODUCTS 2.1 AGGREGATES General: Use materials and gradations that have performed satisfactorily ill prev1ous installations. B. Coarse Aggregate: ASTM D 692, sound; angular crushed stone, crushed gravel, or properly cured, crushed blast-furnace slag. C. Fine Aggregate: ASTM D 1073 sharp-edged natural sand or sand prepared from stone, gravel, properly cured blast-furnace slag, or combinations thereof. 1. For hot-mix asphalt, limit natural sand to a maximum of 20 percent by weight of the total aggregate mass. D. Mineral Filler: ASTM D 242, rock or slag dust, hydraulic cement, or other inert material. 2.2 ASPHALT MATERIALS Asphalt Cement: ASTM D 3381 for viscosity-graded material; ASTM D 946 for penetrationgraded material. SECTION ASPHALT PAVING -2-

3 B. c. 2.3 B. C. Tack Coat: ASTM D 977, emulsified asphalt or ASTM D 2397, cationic emulsified asphalt, slow setting, diluted in water, of suitable grade and consistency for application. Water: Potable. AUXILIARY MATERIALS Herbicide: Commercial chemical for weed control, registered by the EP Provide in granular, liquid, or wettable powder form. Sand: ASTM D 1073, Grade Nos. 2 or 3. Pavement Repair Membrane: PavePrep SA heavy-duty, geo-composite membrane, or equal. D. Joint Sealant: sealant. ASTM D 3405, hot-applied, single-component, polymer-modified bituminous 2.4 MIXES Hot-Mix Asphalt: Provide dense, hot-laid, hot-mix asphalt plant mixes approved by authorities having jurisdiction; designed according to procedures in Al's "Mix Design Methods for Asphalt Concrete and Other Hot-Mix Types"; and complying with the following requirements: 1. Provide mixes with a history of satisfactory performance in geographical area where Project is located. 2. Composition of Mixtures: MoDOT Section with aggregate conforming to Section Sieve Size Percent Passing by Weight Base BP-2 l-inch 3/4-inch 1/2-inch No.4 No.8 No. 30 No Base Course: Total Mineral Aggregate (percent by weight of total mix) Asphalt Cement 3-6 (percent by weight of total mix) 4. Surface Course: Total Mineral Aggregate (percent by weight of total mix) Asphalt Cement (percent by weight of total mix) B. Emulsified-Asphalt Slurry: ASTM D 3910, Type 1, consisting of emulsified asphalt, fine aggregate, and mineral fillers. SECTION ASPHALT PAVING -3-

4 PART 3- EXECUTION 3.1 EXAMINATION B. c. Verify that subgrade is dry and in suitable condition to support paving and imposed loads. Proof-roll subbase using heavy, pneumatic-tired rollers to locate areas that are unstable or that require further compaction. Proceed with paving only after unsatisfactory conditions have been corrected. 3.2 COLD MILLING Clean existing pavement surface of loose and deleterious material immediately before cold milling. Remove existing asphalt pavement by cold milling to grades and cross sections indicated. 1. Mill to a depth of 1-1/2 inches or as shown on drawings. 2. Mill to a uniform finished surface free of gouges, grooves, and ridges. 3. Control rate of milling to prevent tearing of existing asphalt course. 4. Repair or replace curbs, manholes, and other construction damaged during cold milling. 5. Excavate and trim unbound-aggregate base course, if encountered, and keep material separate from milled hot-mix asphalt. B. Recycle millings into new asphalt mix or aggregate base with approval by the Engineer. 3.3 PATCHING Hot-Mix Asphalt Pavement: Saw cut perimeter of patch and excavate existing pavement section to sound base. Excavate rectangular or trapezoidal patches, extending 12 inches into adjacent sound pavement, unless otherwise indicated. Cut excavation faces vertically. Remove excavated material. Recompact existing unbound-aggregate base course to form new subgrade. 1. Portland Cement Concrete Pavement: Remove broken concrete prior to repair B. Tack Coat: Apply uniformly to vertical surfaces abutting or projecting into new, hot-mix asphalt paving at a rate of 0.05 to 0.15 gal.! sq. yd.. 1. Allow tack coat to cure undisturbed before applying hot-mix asphalt paving. 2. Avoid smearing or staining adjoining surfaces, appurtenances, and surroundings. Remove spillages and clean affected surfaces. C. Patching: Fill excavated pavements with hot-mix asphalt base mix and, while still hot, compact flush with adjacent surface. 3.4 REPAIRS Leveling Course: Install and compact leveling course consisting of hot-mix asphalt surface course to level sags and fill depressions deeper than 1 inch in existing pavements. 1. Install leveling wedges in compacted lifts not exceeding 3 inches thick. B. Crack and Joint Filling: Remove existing joint filler material from cracks or joints to a depth of 114 inch. SECTION ASPHALT PAVING -4-

5 1. Clean cracks and joints in existing hot-mix asphalt pavement. 2. Use hot-applied joint sealant to seal cracks and joints less than 114 inch wide. Fill flush with surface of existing pavement and remove excess. 3. Repair cracks and joints more than 1/4- inch wide with membrane. 3.5 SURF ACE PREPARATION A General: Immediately before placing asphalt materials, remove loose and deleterious material from substrate surfaces. Ensure that prepared sub grade is ready to receive paving. 1. Sweep loose' granular particles from surface of unbound-aggregate base course. Do not dislodge or disturb aggregate embedded in compacted surface of base course. B. Herbicide Treatment: Apply herbicide according to manufacturer's recommended rates and written application instructions. Apply to dry, prepared subgrade or surface of compactedaggregate base before applying paving materials. C. Tack Coat: Apply uniformly to surfaces of existing pavement at a rate of 0.05 to 0.15 gal./sq. yd.. 1. Allow tack coat to cure undisturbed before applying hot-mix asphalt paving. 2. Avoid smearing or staining adjoining surfaces, appurtenances, and surroundings. Remove spillages and clean affected surfaces. 3.6 CRACK REP AIR MEMBRANE INSTALLATION A Install repair membrane according to manufacturer's written instructions and as follows: 1. Mill surface of crack as shown on drawings and to provide a surface with a texture less than 1/4" deep. 2. Prepare repair area by cleaning with high-pressure, oil-free and moisture-free compressed air to remove dirt, dust, debris and vegetation. 3. Seal crack with hot-applied sealant. 4. Strictly follow the manufacturer's specifications for temperature requirements and the need for surface primer. 5. Apply membrane to clean, dry and level surface. Pressure roll prior to installing patch material. 3.7 HOT-.MIX ASPHALT PLACING A Machine place hot-mix asphalt on prepared surface, spread uniformly, and strike off. Place asphalt mix by hand to areas inaccessible to equipment in a manner that prevents segregation of rmx. Place each course to required grade, cross section, and thickness when compacted. 1. Place hot-mix asphalt base course in number of lifts and thicknesses indicated. 2. Place hot-mix asphalt surface course in single lift. 3. Spread mix at minimum temperature of 250 deg F. 4. Begin applying mix along centerline of crown for crowned sections and on high side of one-way slopes, unless otherwise indicated. For overlays, offset new joints from existing by at least 5 feet. 5. Regulate paver machine speed to obtain smooth, continuous surface free of pulls and tears in asphalt-paving mat. SECTION ASPHALT PAVING -5-

6 B. Place paving in consecutive strips not less than 10 feet wide unless infill edge strips of a lesser width are required. 1. After first strip has been placed and rolled, place succeeding strips and extend rolling to overlap previous strips. Complete a section of asphalt base course before placing asphalt surface course. C. Promptly correct surface irregularities in paving course behind paver. Use suitable hand tools to remove excess material forming high spots. Fill depressions with hot-mix asphalt to prevent segregation of mix; use suitable hand tools to smooth surface. 3.8 JOINTS Construct joints to ensure a continuous bond between adjoining paving sections. Construct joints free of depressions with same texture and smoothness as other sections of hot-mix asphalt course. 1. Offset overlay joints a minimum of 12 inches from existing joints or install pavements strips perpendicular to existing joints (parking lots only). 2. Clean contact surfaces and apply tack coat to joints. 3. Offset longitudinal joints, in successive courses, a minimum of 6 inches. 4. Offset transverse joints, in successive courses, a minimum of24 inches. 5. Construct transverse joints as described in AI MS-22, "Construction of Hot Mix Asphalt Pavements." 6. Compact joints as soon as hot-mix asphalt will bear roller weight without excessive displacement. 7. Compact asphalt at joints to a density within 2 percent of specified course density. 3.9 COMPACTION General: Begin compaction as soon as placed hot-mix paving will bear roller weight without excessive displacement. Compact hot-mix paving with hot, hand tampers or vibratory-plate compactors in areas inaccessible to rollers. 1. Complete compaction before mix temperature cools to 185 deg F. B. Breakdown Rolling: Complete breakdown or initial rolling immediately after rolling joints and outside edge. Examine surface immediately after breakdown rolling for indicated crown, grade, and smoothness. Correct laydown and rolling operations to comply with requirements. C. Intermediate Rolling: Begin intermediate rolling immediately after breakdown rolling while hot-mix asphalt is still hot enough to achieve specified density. Continue rolling until hot-mix asphalt course has been uniformly compacted to the following density: 1. Average Density: 92 percent of reference maximum theoretical density according to ASTM D 2041, but not less than 90 percent nor greater than 96 percent. D. Finish Rolling: Finish roll paved surfaces to remove roller marks while hot-mix asphalt is still warm. E. Edge Shaping: While surface is being compacted and finished, trim edges of pavement to proper alignment. Bevel edges while asphalt is still hot; compact thoroughly. SECTION ASPHALT PAVING -6-

7 F. Repairs: Remove paved areas that are defective or contaminated with foreign materials and replace with fresh, hot-mix asphalt. Compact by rolling to specified density and surface smoothness. G. Protection: After final rolling, do not permit vehicular traffic on pavement until it has cooled and hardened. H. Erect barricades to protect paving from traffic until mixture has cooled enough not to become marked INSTALLATION TOLERANCES Thickness: Compact each course to produce the thickness indicated within the following tolerances: 1. Base Course: Plus or minus 1/2 inch. 2. Surface Course: Plus 114 inch, no minus. B. Surface Smoothness: Compact each course to produce a surface smoothness within the following tolerances as determined by using a 10-foot straightedge applied transversely or longitudinally to paved areas: 1. Base Course: 1/4 inch. 2. Surface Course: 1/8 inch FIELD QUALITY CONTROL Testing Agency: Engage a qualified independent testing and inspecting agency to perform field tests and inspections and to prepare test reports. 1. Testing agency will conduct and interpret tests and state in each report whether tested Work complies with or deviates from specified requirements. B. Additional testing and inspecting, at Contractor's expense, will be performed to determine compliance of replaced or additional work with specified requirements. C. Thickness: In-place compacted thickness of hot-mix asphalt courses will be determined according to ASTM D D. Surface Smoothness: Finished surface of each hot-mix asphalt course will be tested for compliance with smoothness tolerances. E. In-Place Density: Testing agency will take samples of uncompacted paving mixtures and compacted pavement according to ASTM D Reference maximum theoretical density will be determined by averaging results from four samples of hot-mix asphalt-paving mixture delivered daily to site, prepared according to ASTM D 2041, and compacted according to job-mix specifications. 2. In-place density of compacted pavement will be determined by testing core samples according to ASTM D 1188 or ASTM D a. One core sample will be taken for every 1000 sq. yd. or less of installed pavement, with no fewer than 3 cores taken. SECTION ASPHALT PAVING -7-

8 b. Field density of in-place compacted pavement may also be determined by nuclear method according to ASTM D 2950 and correlated with ASTM D 1188 or ASTMD2726. F. Remove and replace or install additional hot-mix asphalt where test results or measurements indicate that it does not comply with specified requirements DISPOSAL Except for material indicated to be recycled, remove excavated materials from Project site and legally dispose of them in an EPA-approved landfill. 1. Do not allow excavated materials to accumulate on-site. END OF SECTION SECTION ASPHALT PAVING -8-

9 SECTION CONCRETE PAVING PART 1- GENERAL 1.1 RELATED DOCUMENTS Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 01 Specification Sections, apply to this Section. 1.2 SUMMARY Section Includes: 1. Concrete Pavement for Airfields. 2. Concrete Repair. B. Related Sections: 1. Section "Concrete Paving Joint Sealants" for joint sealants in expansion and contraction joints within concrete paving and in joints between concrete paving and asphalt paving or adjacent construction. 1.3 DEFINITIONS Cementitious Materials: Portland cement alone or in combination with one or more of blended hydraulic cement, fly ash and other pozzolans, and ground granulated blast-furnace slag. 1.4 ACTION SUBMITTALS Product Data: For each type of product indicated. B. Shop Drawings: Indicate pavement markings, lane separations, and defmed parking spaces. C. Other Action Submittals: 1. Design Mixtures: For each concrete paving mixture. Include alternate design mixtures when characteristics of materials, Project conditions, weather, test results, or other circumstances warrant adjustments. 1.5 INFORMATIONAL SUBMITTALS Material Certificates: For the following, from manufacturer: 1. Cementitious materials. 2. Steel reinforcement and reinforcement accessories. CONCRETE PAVING

10 3. Admixtures. 4. Curing compounds. 5. Bonding agent or epoxy adhesive. 6. Joint fillers. B. Material Test Reports: For each of the following: 1. Aggregates. Include service-record data indicating absence of deleterious expansion of concrete due to alkali-aggregate reactivity. C. Field quality-control reports. 1.6 QUALITY ASSURANCE Installer Qualifications: An experienced installer who has completed pavement work similar in material, design, and extent to that indicated for this Project and whose work has resulted in construction with a record of successful in-service performance. B. Ready-Mix-Concrete Manufacturer Qualifications: A firm experienced in manufacturing readymixed concrete products and that complies with ASTM C 94/C 94M requirements for production facilities and equipment. 1. Manufacturer certified according to NRMCA's "Certification of Ready Mixed Concrete Production Facilities" (Quality Control Manual - Section 3, "Plant Certification Checklist"). C. Testing Agency Qualifications: Qualified according to ASTM C 1077 and ASTM E 329 for testing indicated. 1. Personnel conducting field tests shall be qualified as ACI Concrete Field Testing Technician, Grade 1, according to ACI CP-1 or an equivalent certification program. D. Concrete Testing Service: Engage a qualified testing agency to perform material evaluation tests and to design concrete mixtures. E. ACI Publications: Comply with ACI 301 unless otherwise indicated. F. Preinstallation Conference: Conduct conference at Pre-Construction Meeting (unless requested otherwise by the Contractor). 1. Review methods and procedures related to concrete paving, including but not limited to, the following: a. Concrete mixture design. b. Quality control of concrete materials and concrete paving construction practices. 2. Require representatives of each entity directly concerned with concrete paving to attend, including the following: a. Contractor's superintendent. b. Independent testing agency responsible for concrete design mixtures. CONCRETE PAVING

11 c. Ready-mix concrete manufacturer. d. Concrete paving subcontractor PROJECT CONDITIONS Traffic Control: Maintain access for vehicular and pedestrian traffic as required for other construction and owner activities. PART 2 -PRODUCTS 2.1 STEEL REINFORCEMENT Reinforcing Bars: ASTM A 615, Grade 60; deformed. B. Epoxy-Coated, Joint Dowel Bars: ASTM A 775; with ASTM A 615, Grade 60, plain-steel bars. C. Tie Bars: ASTM A 615, Grade 60, deformed. D. Hook Bolts: ASTM A 307, Grade A, internally and externally threaded. Design hook-bolt joint assembly to hold coupling against paving form and in position during concreting operations, and to permit removal without damage to concrete or hook bolt. E. Bar Supports: Bolsters, chairs, spacers, and other devices for spacing, supporting, and fastening reinforcing bars, welded wire reinforcement, and dowels in place. Manufacture bar supports according to CRSI's "Manual of Standard Practice" from steel wire, plastic, or precast concrete of greater compressive strength than concrete specified, and as follows: 1. Equip wire bar supports with sand plates or horizontal runners where base material will not support chair legs. 2. For epoxy-coated reinforcement, use epoxy-coated or other dielectric-polymer-coated wire bar supports. F. Epoxy Repair Coating: Liquid, two-part, epoxy repair coating, compatible with epoxy coating on reinforcement. 2.2 CONCRETE MATERIALS Cementitious Material: Use the following cementitious materials, of same type, brand, and source throughout Project: 1. Portland Cement: ASTM C 150, portland cement Type I. B. Normal-Weight Aggregates: ASTM C 33, Class 4S, uniformly graded. Provide aggregates from a single source with documented service-record data of at least 10 years' satisfactory service in similar paving applications and service conditions using similar aggregates and cementitious materials. 1. Maximum Coarse-Aggregate Size: 1-1/2 inches nominal. CONCRETE PAVING

12 2. Fine Aggregate: Free of materials with deleterious reactivity to alkali in cement. C. Water: Potable and complying with ASTM C 94. D. Air-Entraining Admixture: ASTM C 260. E. Chemical Admixtures: Admixtures certified by manufacturer to be compatible with other admixtures and to contain not more than 0.1 percent water-soluble chloride ions by mass of cementitious material. 1. Water-Reducing Admixture: ASTM C 494, Type 2. Retarding Admixture: ASTM C 494, Type B. 3. Water-Reducing and Retarding Admixture: ASTM C 494, Type D. 4. High-Range, Water-Reducing Admixture: ASTM C 494, Type F. 5. High-Range, Water-Reducing and Retarding Admixture: ASTM C 494, Type G. 6. Plasticizing and Retarding Admixture: ASTM C 1017, Type II. 2.3 CURING MATERIALS White, Waterborne, Membrane-Forming Curing Compound: ASTM C 309, Type 2, Class B, dissipating. 1. Products: Subject to compliance with requirements, available products that may be incorporated into the Work include, but are not limited to, the following: a. ChemMasters; Safe-Cure b. Conspec by Dayton Superior; D.O.T. Resin Cure White. c. L&M Construction Chemicals, Inc.; L&M CURE R-2. d. Meadows, W. R., Inc.; 1100-WHITE SERIES. 2.4 RELATED MATERIALS Joint Fillers: ASTM D 1751, asphalt-saturated cellulosic fiber in preformed strips. B. Bonding Agent: ASTM C 1059, Type II, non-redispersible, acrylic emulsion or styrene butadiene. C. Form-Release Agent: Commercially formulated form-release agent that will not bond with, stain, or adversely affect concrete surfaces and that will not impair subsequent treatments of concrete surfaces. D. High-Strength, Non-Shrink Epoxy Patching Mortar: 1. Dayton Superior: Pro-Poxy Approved Equal. CONCRETE PAVING

13 2.5 CONCRETE MIXTURES Prepare design mixtures, proportioned according to ACI 301, for each type and strength of normal-weight concrete, and as determined by either laboratory trial mixtures or field expenence. 1. When automatic machine placement is used, determine design mixtures and obtain laboratory test results that meet or exceed requirements. B. Proportion mixtures to provide normal-weight concrete with the following properties: 1. Compressive Strength (28 Days): 5000 psi. 2. Maximum Water-Cementitious Materials Ratio at Point of Placement: Slump Limit: 4 inches, plus or minus 1 inch. C. Add air-entraining admixture at manufacturer's prescribed rate to result in normal-weight concrete at point of placement having an air content as follows: 1. Air Content: 5-1/2 percent plus or minus 1.5 percent for 1-1/2-inch nominal maximum aggregate size. D. Limit water-soluble, chloride-ion content in hardened concrete to 0.15 percent by weight of cement. E. Chemical Admixtures: Use admixtures according to manufacturer's written instructions. 1. Use water-reducing and retarding admixture when required by high temperatures, low humidity, or other adverse placement conditions. 2.6 CONCRETE MIXING Ready-Mixed Concrete: Measure, batch, and mix concrete materials and concrete according to ASTM C 94. Furnish batch certificates for each batch discharged and used in the Work. 1. When air temperature is between 85 and 90 deg F, reduce mixing and delivery time from 90 minutes to 75 minutes; when air temperature is above 90 deg F, reduce mixing and delivery time to 60 minutes. 2.7 EQUIPMENT Finishing Equipment: The paver-finisher shall be heavy duty, self-propelled machine designed specifically for paving and finishing high quality concrete pavements. It shall weigh at least 2200 pounds per foot of paving lane width and powered by an engine having at least 6.0 horsepower per foot of lane width. The finishing machine shall be designed and operated to strike off, screed and consolidate the concrete such that laitance on the surface is less than 1/8- inch thick B. Vibrators: Vibrator shall be either internal type with immersed tube or multiple spuds, or surface type vibrating pan or screed. For pavements 8 inches or more thick internal vibrators shall be used. They may be attached to the spreader or the finishing machine, or they may be mounted on a separate carriage. Operating frequency for internal vibrators shall be CONCRETE PAVING

14 between 8,000 and 12,000 vibrations per minute. Average amplitude for internal vibrators shall be inches. For pavements less than 8 inches thick, vibrating surface pans or screeds shall be allowed. Operating frequencies for surface vibrators shall be between 3,000 and 6,000 vibrations per minute. 1. The number, spacing, and frequency shall be as necessary to provide a dense and homogeneous pavement and meet the recommendations of ACI 309, Guide for Consolidation of Concrete. Adequate power to operate all vibrators shall be available on the paver. The vibrators shall be automatically controlled so that they shall be stopped as forward motion ceases. The contractor shall provide an electronic or mechanical means to monitor vibrator status. The checks on vibrator status shall occur a minimum of two times per day or when requested by the Engineer. C. Side Forms: Straight side forms shall be made of steel and shall be furnished in sections not less than 10 feet in length. Forms shall have a depth equal to the pavement thickness at the edge, and a base width equal to or greater than the depth. Flexible or curved forms of proper radius shall be used for curves of 100- foot radius or less. Forms shall be provided with adequate devices for secure settings so that when in place they will withstand, without visible spring or settlement, the impact and vibration of the consolidating and finishing equipment. Forms with battered top surfaces and bent, twisted or broken forms shall not be used. Built-up forms shall not be used, except as approved by the Engineer. The top face of the form shall not vary from a true plane more than 1/8 inch in 10 feet, and the upstanding leg shall not vary more than 1/4 inch. The forms shall contain provisions for locking the ends of abutting sections together tightly for secure setting. Wood forms may be used under special conditions, when approved by the Engineer. 1. PART 3 -EXECUTION 3.1 EXAMINATION Examine exposed subgrades and subbase surfaces for compliance with requirements for dimensional, grading, and elevation tolerances. B. Proof-roll prepared subbase surface below concrete paving to identify soft pockets and areas of excess yielding. 1. Completely proof-roll subbase in one direction and repeat in perpendicular direction. Limit vehicle speed to 3 mph. 2. Proof-roll with a pneumatic-tired and loaded, 10-wheel, tandem-axle dump truck weighing not less than 15 tons. 3. Correct subbase with soft spots and areas of pumping or rutting exceeding depth of 1/2 according to requirements in Section "Earth Moving." C. Proceed with installation only after unsatisfactory conditions have been corrected. CONCRETE PAVING

15 3.2 PREPARATION Remove loose material from compacted subbase surface immediately before placing concrete. 3.3 B. EDGE FORMS AND SCREED CONSTRUCTION Forms shall be set sufficiently in advance of the concrete placement to insure continuous paving operation. After the forms have been set to correct grade, the underlying surface shall be thoroughly tamped, either mechanically or by hand, at both the inside and outside edges of the base of the forms. Forms shall be staked into place sufficiently to maintain the form in position for the method of placement. Install forms to allow continuous progress of work and so forms can remain in place at least 24 hours after concrete placement. Form sections shall be tightly locked and shall be free from play or movement in any direction. The forms shall not deviate from true line by more than 1/8 inch at any joint. Forms shall be so set that they will withstand, without visible spring or settlement, the impact and vibration of the consolidating and finishing equipment. Forms shall be cleaned and oiled prior to the placing of concrete. C. Clean forms after each use and coat with form release agent to ensure separation from concrete without damage. The alignment and grade elevations of the forms shall be checked and corrections made by the Contractor immediately before placing the concrete. 3.4 STEEL REINFORCEMENT General: Comply with CRSI's "Manual of Standard Practice" for fabricating, placing, and supporting reinforcement. B. Clean reinforcement of loose rust and mill scale, earth, ice, or other bond-reducing materials. C. Arrange, space, and securely tie bars and bar supports to hold reinforcement in position during concrete placement. Maintain minimum cover to reinforcement. 3.5 JOINTS General: Form construction, isolation, and contraction joints and tool edges true to line, with faces perpendicular to surface plane of concrete. Construct transverse joints at right angles to centerline unless otherwise indicated. 1. When joining existing paving, place transverse joints to align with previously placed joints unless otherwise indicated. B. Construction Joints: Set construction joints at side and end terminations of paving and at locations where paving operations are stopped for more than one-half hour unless paving terminates at isolation joints. 1. Continue steel reinforcement across construction joints unless otherwise indicated. Do not continue reinforcement through sides of paving strips unless otherwise indicated. 2. Provide tie bars at sides of paving strips where indicated. CONCRETE PAVING

16 3. Butt Joints: Use bonding agent at joint locations where fresh concrete is placed against hardened or partially hardened concrete surfaces. 4. Doweled Joints: Install dowel bars and support assemblies at joints where indicated. Lubricate or coat with asphalt one-half of dowel length to prevent concrete bonding to one side of joint. 5. Transverse construction joints shall be installed at the end of each day's placing operations and at any other points within a paving lane when concrete placement is interrupted for more than 30 minutes or it appears that the concrete will obtain its initial set before fresh concrete arrives. The installation of the joint shall be located at a planned contraction or expansion joint. If placing of the concrete is stopped, the Contractor shall remove the excess concrete back to the previous planned joint. C. Isolation Joints: Form isolation joints of preformed joint-filler strips abutting concrete curbs, catch basins, manholes, inlets, structures, other fixed objects, and where indicated. 1. Locate expansion joints at intervals of 50 feet unless otherwise indicated. 2. Extend joint fillers full width and depth of joint. 3. Terminate joint filler not less than 1/2 inch or more than 1 inch below finished surface if joint sealant is indicated. 4. Place top of joint filler flush with finished concrete surface if joint sealant is not indicated. 5. Furnish joint fillers in one-piece lengths. Where more than one length is required, lace or clip joint-filler sections together. 6. During concrete placement, protect top edge of joint filler with metal, plastic, or other temporary preformed cap. Remove protective cap after concrete has been placed on both sides of joint. D. Contraction Joints: Form weakened-plane contraction joints, sectioning concrete into areas as indicated. Construct contraction joints for a depth equal to at least one-fourth of the concrete thickness, as follows: 1. Sawed Joints: Form contraction joints with power saws equipped with shatterproof abrasive or diamond-rimmed blades. Cut 1/8-inch- wide joints into concrete when cutting action will not tear, abrade, or otherwise damage surface and before developing random contraction cracks. a. Tolerance: Ensure that sawed joints are within 1 inch either way from centers of dowels. 2. Doweled Contraction Joints: Install dowel bars and support assemblies at joints where indicated. Lubricate or coat with asphalt one-half of dowel length to prevent concrete bonding to one side of joint. E. Edging: After initial floating, tool edges of paving, gutters, curbs, and joints in concrete with an edging tool to a 1/4-inch radius. Repeat tooling of edges after applying surface finishes. Eliminate edging-tool marks on concrete surfaces. CONCRETE PAVING

17 3.6 CONCRETE PLACEMENT Before placing concrete, inspect and complete formwork installation, steel reinforcement, and items to be embedded or cast-in. B. Remove snow, ice, or frost from subbase surface and steel reinforcement before placing concrete. Do not place concrete on frozen surfaces. C. Moisten subbase to provide a uniform dampened condition at time concrete is placed. Do not place concrete around manholes or other structures until they are at required finish elevation and alignment. D. Comply with ACI 301 requirements for measuring, mixing, transporting, and placing concrete. E. Do not add water to concrete during delivery or at Project site. Do not add water to fresh concrete after testing. F. Deposit and spread concrete in a continuous operation between transverse joints. Do not push or drag concrete into place or use vibrators to move concrete into place. G. Consolidate concrete according to ACI 301 by mechanical vibrating equipment supplemented by hand spading, rodding, or tamping. 1. Consolidate concrete along face of forms and adjacent to transverse joints with an internal vibrator. Keep vibrator away from joint assemblies, reinforcement, or side forms. Use only square-faced shovels for hand spreading and consolidation. Consolidate with care to prevent dislocating reinforcement dowels and joint devices. H. Screed paving surface with a straightedge and strike off. I. Commence initial floating using bull floats or darbies to impart an open-textured and uniform surface plane before excess moisture or bleed water appears on the surface. Do not further disturb concrete surfaces before beginning finishing operations or spreading surface treatments. J. Straightedge Testing and Surface Correction: After the pavement has been struck off and while the concrete is still plastic, it shall be tested for trueness with a Contractor furnished 16-foot straightedge swung from handles 3 feet longer than one-half the width of the slab. The straightedge shall be held in contact with the surface in successive positions parallel to the centerline and the whole area gone over from one side of the slab to the other, as necessary. Advancing shall be in successive stages of not more than one-half the length of the straightedge. Any excess water and laitance in excess of 1/8-inch thick shall be removed from the surface of the pavement and wasted. Any depressions shall be immediately filled with freshly mixed concrete, struck off, consolidated, and refinished. High areas shall be cut down and refinished. Special attention shall be given to assure that the surface across joints meets the smoothness requirements of paragraph 5.2B(3). Straightedge testing and surface corrections shall continue until the entire surface is found to be free from observable departures from the straightedge and until the slab conforms to the required grade and cross section. The use of long- handled wood floats shall be confined to a minimum; they may be used only in emergencies and in areas not accessible to finishing equipment. CONCRETE PAVING

18 K. Cold-Weather Placement: Protect concrete work from physical damage or reduced strength that could be caused by frost, freezing, or low temperatures. Comply with ACI and the following: 1. When air temperature has fallen to or is expected to fall below 40 deg F, uniformly heat water and aggregates before mixing to obtain a concrete mixture temperature of not less than 50 deg F and not more than 80 deg F at point of placement. 2. Do not use frozen materials or materials containing ice or snow. 3. Do not use calcium chloride, salt, or other materials containing antifreeze agents or chemical accelerators unless otherwise specified and approved in design mixtures. L. Hot-Weather Placement: Comply with ACI 301 and as follows when hot-weather conditions exist: 1. Cool ingredients before mixing to maintain concrete temperature below 90 deg F at time of placement. Chilled mixing water or chopped ice may be used to control temperature, provided water equivalent of ice is calculated in total amount of mixing water. Using liquid nitrogen to cool concrete is Contractor's option. 2. Cover steel reinforcement with water-soaked burlap so steel temperature will not exceed ambient air temperature immediately before embedding in concrete. 3. Fog-spray forms, steel reinforcement, and subgrade just before placing concrete. Keep sub grade moisture uniform without standing water, soft spots, or dry areas. 3.7 FLOAT FINISHING General: Do not add water to concrete surfaces during finishing operations. B. Float Finish: Begin the second floating operation when bleed-water sheen has disappeared and concrete surface has stiffened sufficiently to permit operations. Float surface with power-driven floats or by hand floating if area is small or inaccessible to power units. Finish surfaces to true planes. Cut down high spots and fill low spots. Refloat surface immediately to uniform granular texture. 1. Medium-to-Fine-Textured Broom Finish: Draw a soft-bristle broom across float-finished concrete surface perpendicular to line of traffic to provide a uniform, fme-line texture. 3.8 CONCRETE PROTECTION AND CURING B. c. General: Protect freshly placed concrete from premature drying and excessive cold or hot temperatures. Comply with ACI for cold-weather protection. Evaporation Retarder: Apply evaporation retarder to concrete surfaces if hot, dry, or windy conditions cause moisture loss approaching 0.2 lb/sq. ft. x h before and during finishing operations. Apply according to manufacturer's written instructions after placing, screeding, and bull floating or darbying concrete but before float finishing. CONCRETE PAVING

19 D. Begin curing after finishing concrete but not before free water has disappeared from concrete surface. E. Curing Methods: Cure concrete by curing compound as follows: 1. Curing Compound: Apply uniformly in continuous operation by power spray or roller according to manufacturer's written instructions. Recoat areas that have been subjected to heavy rainfall within three hours after initial application. Maintain continuity of coating, and repair damage during curing period. 3.9 PAVING TOLERANCES Comply with tolerances in ACI 117 and as follows: 1. Elevation: 1/4 inch. 2. Thickness: Plus 3/8 inch, minus 1/4 inch. 3. Surface: Gap below 16-foot-long, unleveled straightedge not to exceed 1/4 inch. 4. Alignment of Tie-Bar End Relative to Line Perpendicular to Paving Edge: 1/4 inch per 12 inches of tie bar. 5. Lateral Alignment and Spacing of Dowels: 1 inch. 6. Vertical Alignment ofdowels: 1/4 inch. 7. Alignment of Dowel-Bar End Relative to Line Perpendicular to Paving Edge: 1/4 inch per 12 inches of dowel. 8. Joint Spacing: 3 inches. 9. Contraction Joint Depth: Plus 1/4 inch, no minus. 10. Joint Width: Plus 1/8 inch, no minus FIELD QUALITY CONTROL Testing Agency: Engage a qualified testing agency to perform tests and inspections. B. Testing Services: Testing of composite samples of fresh concrete obtained according to ASTM C 172 shall be performed according to the following requirements: 1. Testing Frequency: Obtain at least one composite sample for each 100 cu. yd or fraction thereof of each concrete mixture placed each day. a. When frequency of testing will provide fewer than five compressive-strength tests for each concrete mixture, testing shall be conducted from at least five randomly selected batches or from each batch if fewer than five are used. 2. Slump: ASTM C 143; one test at point of placement for each composite sample, but not less than one test for each day's pour of each concrete mixture. Perform additional tests when concrete consistency appears to change. 3. Air Content: ASTM C 231, pressure method; one test for each composite sample, but not less than one test for each day's pour of each concrete mixture. 4. Concrete Temperature: ASTM C 1064; one test hourly when air temperature is 40 deg F and below and when it is 80 deg F and above, and one test for each composite sample. CONCRETE PAVING

20 5. Compression Test Specimens: AS1M C 31/C 31M; cast and laboratory cure one set of three standard cylinder specimens for each composite sample. 6. Compressive-Strength Tests: ASTM C 39/C 39M; test one specimen at seven days and two specimens at 28 days. a. A compressive-strength test shall be the average compressive strength from two specimens obtained from same composite sample and tested at 28 days. C. Strength of each concrete mixture will be satisfactory if average of any three consecutive compressive-strength tests equals or exceeds specified compressive strength and no compressive-strength test value falls below specified compressive strength by more than 500 psi. D. E. F. G. H. I. Test results shall be reported in writing to Engineer, concrete manufacturer, and Contractor within 48 hours of testing. Reports of compressive-strength tests shall contain Project identification name and number, date of concrete placement, name of concrete testing and inspecting agency, location of concrete batch in Work, design compressive strength at 28 days, concrete mixture proportions and materials, compressive breaking strength, and type of break for both 7- and 28-day tests. Nondestructive Testing: Impact hammer, sonoscope, or other nondestructive device may be permitted by Engineer but will not be used as sole basis for approval or rejection of concrete. Additional Tests: Testing and inspecting agency shall make additional tests of concrete when test results indicate that slump, air entrainment, compressive strengths, or other requirements have not been met, as directed by Engineer. Concrete paving will be considered defective if it does not pass tests and inspections. Additional testing and inspecting, at Contractor's expense, will be performed to determine compliance of replaced or additional work with specified requirements. Prepare test and inspection reports REP AIRS AND PROTECTION General: New pavement slabs that are broken or contain cracks shall be removed and replaced or repaired, as specified hereinafter at no cost to the owner. 1. Spalls along joints shall be repaired as specified. 2. Removal of partial slabs is not permitted. Removal and replacement shall be full depth, shall be full width of the slab, and the limit of removal shall be normal to the paving lane and to each original transverse joint. 3. The engineer will determine whether cracks extend full depth of the pavement and may require cores to be drilled on the crack to determine depth of cracking. Such cores shall be 4-inch diameter, shall be drilled by the Contractor and shall be filled by the Contractor with a well consolidated concrete mixture bonded to the walls of the hole with epoxy resin, using approved procedures. Drilling of cores and refilling holes shall be at no expense to the owner. All epoxy resin used in this work shall confmm to ASTM C 881, Type V. CONCRETE PAVING

21 B. Shrinkage Cracks: Shrinkage cracks, which do not exceed 2 inches in depth, shall be cleaned and then pressure injected with epoxy resin, Type N, Grade 1, using procedures as approved. Care shall be taken to assure that the crack is not widened during epoxy resin injection. All epoxy resin injection shall take place in the presence of the Engineer. Shrinkage cracks, which exceed 2 inches in depth, shall be treated as full depth cracks. C. Slabs With Cracks through Interior Areas: 1. Interior area is defined as that area more than 6 inches from either adjacent original transverse joint. 2. The full slab shall be removed and replaced at no cost to the owner, when there are any full depth cracks, or cracks greater than 2" in depth, that extend into the interior area. D. Cracks Near and Parallel to Transverse Joints: All cracks essentially parallel to original transverse joints, extending full depth of the slab, and lying wholly within 6 inches either side of the joint shall be treated as specified hereinafter. Any crack extending more than 6 inches from the transverse joint shall be treated as specified above in subparagraph "Slabs With Cracks Through Interior Area." 1. Full Depth Cracks Present, Original Joint Not Opened: When the original uncracked transverse joint has not opened, the crack shall be sawed and sealed, and the original transverse joint filled with epoxy resin as specified below. The crack shall be sawed with equipment specially designed to follow random cracks. The reservoir for joint sealant in the crack shall be formed by sawing to a depth of 3/4 inch, plus or minus 1/16 inch, and to a width of 5/8 inch, plus or minus 1/8 inch. Any equipment or procedure which causes raveling or spalling along the crack shall be modified or replaced to prevent such raveling or spalling. The joint sealant shall be a liquid sealant as specified. Installation of joint seal shall be as specified for sealing joints or as directed. If the joint sealant reservoir has been sawed out, the reservoir and as much of the lower saw cut as possible shall be filled with epoxy resin, Type N, Grade 2, thoroughly tooled into the void using approved procedures. If only the original narrow saw cut has been made, it shall be cleaned and pressure injected with epoxy resin, Type N, Grade 1, using approved procedures. If filler type material has been used to form a weakened plane in the transverse joint, it shall be completely sawed out and the saw cut pressure injected with epoxy resin, Type N, Grade 1, using approved procedures. Where a parallel crack goes part way across paving lane and then intersects and follows the original transverse joint which is cracked only for the remained of the width, it shall be treated as specified above for a parallel crack, and the cracked original joint shall be prepared and sealed as originally designed. 2. Full Depth Cracks Present, Original Transverse Joint Also Cracked: At a transverse joint, if there is any place in the lane width where a parallel crack and a cracked portion of the original joint overlap, the entire slab containing the crack shall be removed and replaced for the full lane width and length. E. Removal and Replacement of Full Slabs: Where it is necessary to remove full slabs, unless there are keys or dowels present, all edges of the slab shall be cut full depth with a concrete saw. All saw cuts shall be perpendicular to the slab surface. If dowels, or tie bars are present along any edges, these edges shall be sawed full depth 24 inches from the edge if only keys are present, or just beyond the end of the dowels or tie bars if they are present. CONCRETE PAVING

22 These joints shall then be carefully sawed on the joint line to within 1 inch of the depth of the dowel. 1. The main slab shall be further divided by sawing full depth, at appropriate locations, and each piece lifted out and removed. Suitable equipment shall be used to provide a truly vertical lift, and approved safe lifting devices used for attachment to the slabs. The narrow strips along keyed or doweled edges shall be carefully broken up and removed using light, hand-held jackhammers, 30 pound or less, or other approved similar equipment. 2. Care shall be taken to prevent damage to the dowels, tie bars, or keys or to concrete to remain in place. The joint face below keys or dowels shall be suitably trimmed so that there is not abrupt offset in any direction greater than 1/2 inch and no gradual offset greater than 1 inch when tested in a horizontal direction with a 12 foot straightedge. 3. No mechanical impact breakers, other than the above hand-held equipment shall be used for any removal of slabs. If underbreak between 1-1/2 and 4 inches deep occurs at any point along any edge, the area shall be repaired as directed before replacing the removed slab. Procedures directed will be similar to those specified for surface spalls, modified as necessary. 4. If underbreak over 4 inches deep occurs, the entire slab containing the underbreak shall be removed and replaced. Where there are no dowels, tie bars, or keys on an edge, or where they have been damaged, dowels of the size and spacing as specified for other joints in similar pavement shall be installed by epoxy grouting them into holes drilled into the existing concrete using procedures as specified. Original damaged dowels or tie bars shall be cut off flush with the joint face. Protruding portions of dowels shall be painted and lightly oiled. All 4 edges of the new slab shall thus contain dowels or original keys or original tie bars. 5. Placement of concrete shall be as specified for original construction. Prior to placement of hew concrete, the underlying material (unless it is stabilized) shall be recompacted and shaped as specified in the appropriate section of these specifications. The surfaces of all four joint faces shall be cleaned of all loose material and contaminants and coated with a double application of membrane forming curing compound as bond breaker. Care shall be taken to prevent any curing compound from contacting dowels or tie bars. The resulting joints around the new slab shall be prepared and sealed as specified for original construction. F. Repairing Spalls Along Joints: Where directed, spalls along joints of new slabs, and along parallel cracks used as replacement joints, shall be repaired by first making a vertical saw cut at least 1 inch outside the spalled area and to a depth of at least 2 inches. 1. Saw cuts shall be straight lines forming rectangular areas. The concrete between the saw cut and the joint, or crack, shall be chipped out to remove all unsound concrete and at least 112 inch of visually sound concrete. The cavity thus formed shall be thoroughly cleaned with high-pressure water jets supplemented with compressed air to remove all loose material. 2. Immediately before filling the cavity, a prime coat of epoxy resin, Type III, Grade I, shall be applied to the dry cleaned surface of all sides and bottom of the cavity, except any joint face. The prime coat shall be applied in a thin coating and scrubbed into the surface with a stiff-bristle brush. Pooling of epoxy resin shall be avoided. 3. The cavity shall be filled with epoxy resin mortar. Concrete shall be used for larger spalls, generally those more than 1/2 cu. ft. in size, and mortar shall be used for the CONCRETE PAVING