SECTION 02513

ASPHALT CONCRETE PAVING

PART 1 - GENERAL

1.1	RELATED DOCUMENTS

A.	Drawings and general provisions of Contract apply to work of this Section.

1.2	DESCRIPTION OF WORK

A.	Extent of asphalt concrete paving work is shown on drawings.

B.	Prepared aggregate subbase and base is specified in "SUBGRADE STABILIZATION," "LIMEROCK" and "SOIL CEMENT" Sections.

C.	Prepared subgrade is specified in "EARTHWORK" Section.

D.	Saw-cutting of edges of existing pavement is specified in site clearing section.

1.3	SUBMITTALS

A.	Material Certificates: Provide copies of materials certificates signed by material producer and Contractor, certifying that each material item complies with, or exceeds, specified requirements.

1.4	QUALITY ASSURANCE

A.	Codes and Standards: Comply with State highway or transportation department standard specifications, latest edition, and with local governing regulations if more stringent than herein specified.

PART 2 - PRODUCTS

2.1	MATERIALS

General: Use locally available materials and gradations which exhibit a satisfactory record of previous installations.

A.	Type S Asphaltic Concrete: FDOT, 331-2, 3, 4, 5.

B.	Type III Cement Asphaltic Concrete: FDOT, 333-2, 3, 4 and 5.

C.	Asphalt Cement: FDOT, 916-1

D.	Prime Coat: Cut-back asphalt grade RC-70 or RC-250 per FDOT 916-2; emulsified asphalt grade SS-1 or SS1H, per FDOT 916-4, diluted in equal proportions with water; or other types and grades of bituminous material.

E.	Tack Coat: Emulsified asphalt; RS-2, SS-1, or SS-1H (diluted in equal proportions with water) per FDOT 916-4. Cut-back asphalt RL-70, or asphalt cement, penetration grade 85-100.

F.	Lane Marking Paint: Chlorinated rubber-alkyd type, AASHTO M 248 (FS TT-P-115), Type III or per FDOT 971-12.2.

G.	Thermoplastic Traffic Stripes and Markings: Per FDOT standard specifications for Road and Bridge Construction, Section 711.

H.	Wheel Stops: Precast of 3,500 psi air-entrained concrete, approximately 6 inches high, and 6 feet 0 inches long, with chamfered corners and drainage slots on underside.

2.2	ASPHALT-AGGREGATE MIXTURE AND PREPARATIONS

A.	FDOT 330-5, and FDOT 330-6.

PART 3 - EXECUTION

3.1	WEATHER LIMITATIONS

A.	Mixture shall not be spread when the air temperature is not greater than 40o F, in the shade (away from artificial heat), or there is evidence of a frozen base, or when the wind is blowing to such an extent that proper and adequate compaction cannot be maintained or when sand, dust, etc., are being deposited on the surface being paved.

Any mixture caught in transit by a sudden rain may be laid only at Contractor's risk. Should such mixture prove unsatisfactory, it shall be removed and replaced at Contractor's expense. In no case shall the mixture be laid while rain is falling or when there is water on the surface to be covered.

3.2	PREPARATION OF ASPHALT CEMENT

A.	Heat the asphalt cement in advance of the mixing operations, to within a range of 270o F to 350o F. Maintain the heating operations constant within these limits. Wide temperature fluctuations during the day will not be permitted.

3.3	PREPARATION OF AGGREGATE

FDOT 330-5

3.4	PREPARATION OF MIXTURE

FDOT 330-6

3.5	TRANSPORTATION OF MIXTURE

Transport the mixture in vehicles clean of foreign material properly equipped to be covered during inclement weather. Coat the inside surfaces of the truck with soapy water or approved emulsion containing less than 5 percent oil (not kerosene, gasoline or similar products) and raise beds to drain excess prior to loading.

3.6	PREPARATION OF APPLICATION SURFACES

A.	Cleaning: Thoroughly clean the surface to be covered of all loose and deleterious material before laying any mixture.

B.	Patching and Leveling Courses: Where a surface course is constructed on an existing pavement or base and/or where called for in the Drawings, apply patching or leveling courses to bring the existing surface to proper grade and cross-section. Prior to spreading leveling courses, all depressions in the existing surface more than one inch deep shall be filled by spot patching with leveling course mixture, and then thoroughly compacted.

C.	Coating Surfaces of Contacting Structures: Paint all structures such as manholes, inlet, valve boxes, etc., with a uniform coating of asphaltic cement.

D.	Prime Coat: Prime materials shall be uniformly applied using a pressure distributor at the minimum rates of 0.10 gallons per square yard for limerock, limerock stabilized and local rock bases, and 0.15 gallons per square yard for sand, clay, shell and shell stabilized bases. The actual amount to be applied shall be dependent on the character of the surface and shall be sufficient to coat the surface thoroughly without having any access to form pools or to flow off the base. The temperature of the prime material shall be that temperature between 100o F and 150o F, which will insure uniform distribution. The moisture content of the base shall not be greater than 90 percent of optimum to obtain adequate penetration.

Apply a light uniform application of cover material and roll with a traffic roller for at least 10 passes before opening to traffic. Where an emulsified asphalt is used for prime coat, the Engineer may require that cover material be hot-asphalt coated with two to four percent asphalt-cement, if necessary, to achieve a prime coat which will remain reasonably intact until the surface course is placed; the application rate shall be approximately 10 pounds per square yard.

3.7	TACK COAT

A tack coat will only be required on primed bases in areas that have become excessively dirty and cannot be cleaned, or in areas where the prime has cured to the extent that it has lost adequate bonding effect. Generally, a tack coat will be required on bituminous base or leveling courses before placing the surface course.

Apply tack, suitably heated, at the minimum rate necessary to bond the wearing surface to the base (between 0.02 and 0.08 gallons per square yard). The upper limit may be exceeded for resurfacing concrete. Apply tack sufficiently in advance of the wearing course to permit drying but not so far in advance to allow loss of adhesiveness from dust and other foreign material. No traffic shall be allowed on the tacked surface.

3.8	PLACING MIXTURE

A.	Mixture shall be placed and spread only after the surface to be overlayed is properly prepared, intact, firm, properly cured and dried. No mixture shall be spread that cannot be finished and compacted during the daylight hours of day of spreading.

Spread the mixture with mechanical spreaders, except where impracticable. A stringline shall be used to obtain an accurate, uniform alignment of the pavement edge. The temperature of the mixture at the time of spreading shall be between 270o F and 350o F.

1.	Checking Depth of Layer: The depth of each layer shall be checked by the Contractor at intervals, not to exceed 25 feet. Any deviation from the required thickness, in excess of the allowable tolerance, shall be immediately corrected.

B.	Surface Courses:

1.	Spreading and Finishing: Immediately upon arrival, the mixture shall be dumped into the spreader, spread and struck-off to the full width required and to such loose dept to secure the specified thickness. Excess mixture shall be carried ahead of the screed at all times. Hand rake behind the machine as required.

2.	Thickness of Layers: Surface courses of thickness greater than two inches, shall be constructed in approximately equal layers and of less than two inches compacted thickness. Each layer shall be thoroughly compacted and shall conform to these specifications prior to overlaying.

3.	Correcting Defects: Prior to rolling, the surface shall be checked, and irregularities adjusted. All drippings, fat sandy accumulations from the screed, and fat spots from any source shall be removed and replaced with satisfactory material. No skin patching shall be done. Where a depression is to be corrected while the mixture is hot, the surface shall be well scarified before the addition of fresh mixture.

C.	Leveling Courses:

1.	Spreading: The initial and intermediate leveling courses shall be placed by a spreader box, working conjunction with two motor graders. The final leveling course shall be placed by a paving machine. However, if the total quantity of leveling to be applied is less than 150 pounds per square yard, the paving machine may not be required.

2.	Application Rates: The application rate of leveling mixture shall not exceed 50 pounds per square yard per course except Type S-1 asphaltic concrete leveling shall not exceed 75 pounds per square yard per course. The actual application rate shall be as required to establish the finished lines and grades shown in the Drawings and shall not be limited to any average or typical rate or thickness which may be shown in the Drawings.

3.	Leveling Over Existing Concrete Pavement: Remove all excess joint filler to flush with the existing pavement. For broken concrete pavement (with or with out existing asphalt surface) the first leveling course shall be placed as soon after, but not later than 2 days after, the cracking and reseating operation.

3.9	COMPACTING MIXTURE

Density required for asphaltic concrete pavement, after final compaction, shall be as least 95 percent of the laboratory compacted density of the paving mixture. Tests shall be performed every 500 feet for roadways and 50,000 square feet for parking areas.

A.	Equipment and Sequence: For each paving or leveling train in operation, the Contractor shall furnish a separate set of rollers, with operators. The rolling shall be done in sequence, and with the equipment as follows, unless otherwise permitted by the Engineer:

1.	Seal Rolling - Use tandem steel rollers weighing 5 to 12 tons, following as close behind the spreaders as is possible without pick-up, undue displacement or blistering of the material.

2.	Rolling with Traffic Roller - Use self-propelled pneumatic-tied rollers, 6 to 10 tons and tire pressure to 55 pounds, following as close behind the seal rolling as the mix will permit. The roller shall cover every portion of the surface with at least five passes.

3.	Final Rolling - Use tandem steel roller, weighing 8 to 12 tons after the pneumatic-
tired rolling has been completed, but before the pavement temperature has dropped below 140o F.

B.	Compaction of Crossovers, Intersections, etc.: Where a separate paving machine is used to pave crossovers, compaction may be done by one 8 to 10 ton tandem steel roller. If crossovers, intersections and acceleration and deceleration lanes are placed with the main run of paving, a traffic roller shall also be used in the compaction.

C.	Rolling Procedures: The rolling shall be longitudinal. Where the lane being placed is adjacent to a previously placed lane, the center joint shall be pinched or rolled, prior to rolling of the rest of the lane. Continue across the mat, overlapping each previous roller path by at least one-half the width of the roller wheel. The motion of the roller shall be slow enough to avoid displacement of the mixture, and any displacement shall be corrected at once by the use of rakes, and the addition of fresh mixture if required. Final rolling shall continue until all roller marks are eliminated.

Self-propelled, pneumatic-tired traffic rollers shall proceed at a speed of 6 to 10 miles per hour; the area covered by each roller shall not exceed 4,000 square yards per hour, except that for Type S-1 Asphaltic Concrete, the maximum shall be 3,000 square yards per hour.

D.	Number of Traffic Rollers Required: A sufficient number of self-propelled pneumatic-
tired rollers shall be used to assure that the rolling will not delay any other phase of the laying operation nor result in excessive cooling of the mixture. In the event that the rolling falls behind, the laying operation shall be discontinued until the rolling operations are sufficiently caught up.

E.	Rolling Patching and Leveling Courses: Use self-propelled pneumatic-tired rollers for all patching and leveling courses. Where the initial leveling course is placed over broken concrete pavement, the pneumatic-tired rollers shall weight at least 15 tons. For Type S-I Asphaltic Concrete leveling courses, use a steel-wheeled roller, to supplement the traffic rollers. The use of a steel-wheeled roller will otherwise be at Contractor's option.

Areas which are inaccessible to a roller (such as areas adjacent to curbs, headers, gutters, manholes, etc.) shall be compacted by the use of hand tamps or other satisfactory means.

F.	Correcting Defects: Rollers shall not deposit gasoline, oil or grease onto the pavement. Any areas damaged by such deposits shall be removed and replaced. While rolling is in progress, the surface shall be tested continuously and all discrepancies corrected to comply with the surface requirements. All drippings, fat or lean areas and defective construction of any description shall be removed and replaced. Depressions which develop before the completion of the rolling shall be remedied by loosening the mixture and adding new mixture to bring the depressions to a true surface. Should any depressions remain after the final compaction has been obtained, the full depth of the mixture shall be removed and replaced with sufficient new mixture to form a true and even surface. All high spots, joints and honeycomb shall be corrected. Any mixture remaining unbonded after rolling shall be removed and replaced. Any mixture which becomes loose or broken, mixed or coated with dirt or in any way defective, prior to laying the wearing course shall be removed and replaced with fresh mixture which shall be immediately compacted to conform with the surrounding area. Areas of defective surface may be repaired by the use of the indirect heat. No method of repair involving open-flame heaters shall be used.

G.	Provisions Applicable to Shoulder Pavement Only: Where sand-asphaltic shoulders are constructed within the limits of curb and gutter, compaction shall be done by light weight rolling equipment, which will not displace the previously constructed curb and gutter.

3.10	JOINTS

A.	Fresh mixture shall be laid against the exposed edges at joints (trimmed or formed as provided below) in close contact with the exposed edge so that an even, well- compacted joint will be produced after rolling.

1.	Transverse Joints: Placing of the mixture shall be as continuous as possible. The roller shall not pass over the unprotected end of the freshly laid mixture except when the laying operation is to be discontinued long enough to permit the mixture to become chilled. When the laying operation is thus interrupted, a transverse joint shall be constructed by cutting back on the previous run to expose the full depth of the mat.

2.	Longitudinal Joints: Where a portion of the width of pavement is to be laid and opened to traffic, longitudinal joints shall be formed by rolling the exposed edge of the strip first laid. When the adjacent strip is constructed, the Engineer may require the edge of the mixture in place to be trimmed back to expose an unsealed or granular vertical surface. Where the strip first laid is closed to traffic, the edge shall not be sealed but shall be left vertical and the adjacent strip placed against it without trimming.

3.11	SURFACE REQUIREMENTS & CORRECTION:

A.	The finished surface shall not vary more than 3/16 inch when measured by rolling or manual straightedge applied parallel to the center line of the pavement. Any surface irregularities exceeding such limits shall be corrected as specified herein.

1.	Manual Straightedging: A 15-foot manual straightedge shall be furnished by the Contractor and shall be available at all times on the work. The Contractor shall designate an employee whose duty it is to handle the straightedge in checking the compacted surfaces.

2.	Texture of Finished Surfaces: The finished surface shall be of uniform texture and compaction. The surface shall have no pulled, torn or loosened portions, and shall be free of sand streaks, sand spots or ripples. (These requirements shall also apply to any areas where it is necessary to apply hand work.) Defective area shall be corrected as follows:

a.	If the correction is made by replacing of the full thickness, it shall extend to at least 50 feet each side of the defective area.

b.	If the correction is made by overlaying, the overlay shall consist of at least 100 pounds of mixture per square yard at the defective section and shall taper uniformly down from the full thickness of such weight, to zero thickness (featheredged) at the end of a minimum length of 50 feet each side of the defective area.

3.12	PROTECTION OF FINISHED SURFACE

A.	Finished surfaces including courses to be overlayed shall be kept clean and no dumping of any material onto the surfaces shall be permitted. Protect pavement against damage during shoulder construction by providing proper attachments to grader blades. Vehicular traffic shall not be permitted until the pavement has set sufficiently to prevent rutting or other distortion.

3.13	TRAFFIC AND LANE MARKINGS

A.	Cleaning: Sweep and clean surface to eliminate loose material and dust.

B.	Striping: Use chlorinated-rubber base traffic lane-marking paint, factory-mixed, quick-
drying, and non-bleeding.

1.	Color: white and yellow as indicated on drawings.

a.	Apply paint with mechanical equipment to produce uniform straight edges. Apply in 2 coats at manufacturer's recommended rates.

3.14	WHEEL STOPS

A.	Secure wheel stops to asphalt concrete surface with not less than two 3/4 inch diameter steel dowels embedded in precast concrete at 1/3 points. Size length of dowel to penetrate at least 6 inches into asphalt concrete. Drill placement holes oversize and embed dowels in hot bituminous grout material.

3.15	FIELD QUALITY CONTROL

A.	THICKNESS REQUIREMENTS & CORRECTIONS

1.	Pavement thickness shall be determined from the length of the core borings as specified herein. The maximum allowable deficiency from the specified thickness and serious deficiency thickness shall be as follows:

a.	Pavement of specified thickness 1 1/2 inches or less

Maximum allowable deficiency	3/16 inch or more

Serious deficiency	1/4 inch or more

b.	Pavement of specified thickness greater than 1 1/2 inches but less than 2 1/2 inches

Maximum allowable deficiency	1/4 inch or more

Serious deficiency	3/8 inch or more

c.	Pavement of specified thickness 2 1/2 inches or greater

Maximum allowable deficiency	1/2 inch or more

Serious deficiency	3/4 inch or more

2.	Contractor shall correct seriously deficient areas either by replacing the full thickness for a length extending at least 50 feet from each end of the deficient area, or (when permitted by the Engineer) by overlaying as specified herein at his own expense.

As an exception to the above, pavement outside a main roadway area (acceleration and deceleration lanes, crossovers and parking areas) may be left in place, without compensation (except for payment for the bituminous material), when so permitted by the Engineer, even though the thickness deficiency exceeds the serious deficiency tolerance specified above.

Where the deficiency exceeds allowable but does not exceed serious, Contractor will be allowed to leave such pavement in place, but without compensation other than for the bituminous material contained therein. The areas of such pavement for which no square yard payment will be made shall be the product of the total distance between acceptable cores, multiplied by the width of the lane which was laid at the particular pass in which deficient thickness was indicated. To determine the extent of the deficiencies, additional cores will be taken as required.

3.	Correcting Deficiency by Adding New Surface Material: For any case of excess deficiency of the pavement, Contractor will be permitted, if approved by the Engineer for each particular location, to correct the deficient thickness by adding new surface material and compacting to the same density as the adjacent surface. The area to be corrected and the thickness of the new material added shall be as specified herein. All costs of the overlaying and compacting shall be borne by the Contractor.

B.	CALCULATION FOR THICKNESS OF PAVEMENT

1.	Core Borings: The thickness of the pavement shall be determined from the length of cores, at least two inches in diameter, taken at random points along the roadway and the parking areas. Each core shall represent a roadway section not longer than 500 feet or a parking area not less than 10,000 square feet. The average thickness shall be determined from the measured thicknesses, and in accordance with the procedure and criteria specified herein.

If it is found that the specified pavement thickness has not been installed per this specification and if Contractor believes that the number of cores taken by the Owner is insufficient to properly indicate the thickness of the pavement, he may request the owner make additional borings at locations designated by him. The cost of these additional borings shall be deducted from any sums due Contractor unless such borings indicate that the pavement within the questioned area is of specified thickness.

2.	Criteria for Calculations:

a.	Average thickness shall be calculated for the total length of project.

b.	When the thickness as measured by the cores is more than 1/2 inch greater than the specified thickness, it shall be considered in the calculation as the specified thickness plus 1/2 inch.

c.	Areas of deficient thickness pavement which are left in place with no compensation shall not be taken into account in the calculations.

d.	Where areas of defective surface or deficient thickness are corrected by overlaying with additional material, the thickness used in the calculations shall be the specified thickness for such areas.

C.	TESTING

1.	The contractor shall provide, at his expense, the following tests before stating any laying operations:

a.	Determination of the job mix formula

b.	Tests of the asphalt cement

c.	Sieve analysis of the aggregate

d.	Determination of bitumen content of the asphalt concrete

END OF SECTION