506 GAP-GRADED STONE MATRIX ASPHALT

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506.01 DESCRIPTION.
Place gap-graded stone matrix asphalt (GGSMA) surface as specified. GGSMA shall conform to Section 504, except as specified.
506.02 MATERIALS.
Gap-Graded Stone Matrix Asphalt Mix       904.05
Production Plants       Section 915
506.03 CONSTRUCTION.
506.03.01 Demonstration. Demonstrate that a satisfactory mix can be produced, placed, and the compactive effort determined before proceeding with the actual work. Place a minimum of 100 tons of GGSMA outside the project limits for the demonstration. A new strip will be required if a project carries over to a new season. Paver and rollers shall conform to 504.03.01. A material transfer vehicle may be used as part of the demonstration strip.
506.03.02 Hauling Units. Use vehicles with tight, clean and smooth metal beds. Lightly coat the beds with an approved asphalt release agent, a combination of release agent/soap solution, or No. 10 dust coated with 1 percent asphalt or uncoated. Do not use petroleum derivatives or other coating materials that may contaminate the characteristics of the mix. Drain the bed before loading. Immediately after loading, cover each load with a full asphalt tarp, securely fastened along the sides and rear of the truck bed. The tarp shall contain no holes or rips.
The time between plant mixing and shipment shall not exceed one hour. Storage time may vary depending upon gradation, type of binder and/or stabilizer. Stored material shall have results of no less quality than mixes discharged directly into hauling vehicles.
506.03.03 Weather Restrictions. Refer to 504.03.02. GGSMA placement will only be permitted when the ambient and surface temperatures are at least 50 F.
506.03.04 Material Transfer Vehicle (MTV). Use a material transfer vehicle to apply the final surface course. The MTV shall perform additional mixing of the GGSMA and then deposit the mix into the paver at a uniform temperature and consistency.
506.03.05 Asphalt Placement. Refer 504.03.06.
506.03.06 Pavement Thickness. The thickness of the pavement shall be as specified. 504.03.13 (Thin Lift) is not applicable to GGSMA.
506.03.07 Tack Coat. Refer to 504.03.04 or 504.03.05 except the resulting coating shall be asphalt applied at a rate of 0.04 gal/yd2 to 0.08 gal/yd2 for Tack Coat. Apply Non-Tracking Tack Coat (NTTC) when specified at a rate of 0.05 gal/yd2 to 0.10 gal/yd2.
506.03.08 Compaction. Compact the GGSMA using a minimum of 3 steel-wheeled rollers, each weighing 10 to 12 tons. The rollers shall be equipped with a plain or soapy watering system to prevent the material from sticking. The rollers shall follow the paver within 500 ft or roll according to the approved Quality Control Plan. Rolling shall start immediately after placement. In-place density shall conform to 504.03.12, except density shall be in accordance with 506.04.01.
506.03.09 Control Strip. The construction of a control strip may be required at any time during of GGSMA placement, based on the evaluation of compaction results.
The Contractor may opt to construct a control strip between 400 ft and 500 ft in length for guidance in determining roller patterns to achieve optimum density. Construct control strips on the first workday in which GGSMA is placed. Based on Contractor evaluation of the initial control strip, paving may continue at risk.
A density pay adjustment will not be assessed for the amount of material required for the control strips. Removal of any control strip shall be at no additional cost.
506.03.10 Verification of Mix Design. Refer to 904.04.05
506.03.11 Verification Evaluation. MSMT 735 and 904.04.06.
506.03.12 Pavement Profile. Refer to Section 535 in the Contract Documents.
506.03.13 Sampling and Testing for Mixture and Density. Refer to 504.03.11 and 504.03.12.
506.04  MEASUREMENT AND PAYMENT.
GGSMA will be measured and paid for at the Contract unit price per ton, complete and in place. The payment will be full compensation for furnishing, hauling, placing all materials, material transfer vehicle, anti-stripping additive, tack coat, control strips, setting of lines and guides where specified, and for all material, labor, equipment, tools, and incidentals necessary to complete the work.
Material produced for the demonstration will not be measured but the cost will be incidental to the GGSMA item.
506.04.01 Payment Adjustment for GGSMA and Pavement Density. Refer to 504.04 except as follows. Payment adjustments for pavement density will be based on individual sublot core test data for a given lot and the lot average density as specified in this section and the following.
TABLE 506 A
GAP Graded Stone Matrix Asphalt Mixes - Percent of Maximum Density
Lot Average % Minimum No Individual Sublot Below % Pay Factor (DF)
95.0 95.0 1.050
94.9 94.8 1.045
94.8 94.6 1.040
94.7 94.4 1.035
94.6 94.2 1.030
94.5 94.0 1.025
94.4 93.8 1.020
94.3 93.6 1.015
94.2 93.4 1.010
94.1 93.2 1.005
94.0 93.0 1.000
93.8 92.7 0.990
93.6 92.4 0.980
93.4 92.1 0.970
93.2 91.8 0.960
93.0 91.5 0.950
92.8 91.2 0.940
92.6 90.9 0.930
92.4 90.6 0.920
92.2 90.3 0.910
92.0 90.0 0.900
91.8 89.7 0.890
91.6 89.4 0.880
91.4 89.1 0.870
91.2 88.8 0.860
91.0 88.5 0.850
Less than 91.0 0.750 rejected per Engineer
Note 1: When any test data is above 97.0, the lot may be rejected per the Engineer. When not rejected, the lot will receive a pay adjustment in accordance with the following:
(a) When the density lot average is above 97.5, the pay factor = 75 percent.
(b) When 3 sublot densities are above 97.0, the pay factor = 95 percent.
(c) When 4 or more sublot densities are above 97.5, the pay factor = 75 percent.
Note 2: When the Contractor's core specific gravity data does not compare with the Administration's core specific gravity data, only the Administration's single sublot values and lot average value will be used in acceptance decision.
Note 3: The average sublot values and the lot average will be used in acceptance decision.
506.04.02 Dispute Resolution. Refer to 915.02.03.