314SUPERPAVE ASPHALT MIXTURE DESIGN, STANDARD CONSTRUCTION, ASPHALT RICH BASE COURSE

CONSTRUCTION, ASPHALT RICH BASE COURSE

314.1DESCRIPTION—This work is the standard construction of a plant -mixed asphalt rich base course

Compactor (SGC) using prescribed manufactured additives, or plant process modifications or both.

314.2MATERIAL—Section 413.2 with the following modifications:

RAS material in ARBC mixtures.

following modifications and additions:

and either WMA Technology additive(s) or modifier(s) in proportions to produce a JMF that conforms to the material, gradation, and volumetric Superpave Asphalt Mixture Design requirements according to Bulletin 27, except as modified in Table 1. Produce an asphalt mixture for the indicated nominal maximum aggregate size (NMAS) and design ESALs except as procedurally modified by the WMA Technology Manufacturer Technical Representative to address laboratory procedures when preparing, compacting and testing asphalt mixtures to achieve a uniform blend. Special additive(s) or modifier(s) need not be used if mixture temperature, workability, and compaction can be achieved solely through plant mechanical modification to produce foamed asphalt. Do not incorporate the WMA Technology additive, modifier, or process during the volumetric asphalt mixture design process, so that the JMF volumetrics and material percentages are based on a mixture with no WMA Technology. Only use the WMA Technology additive, modifier, or process to evaluate results from moisture susceptibility testing during the mix design process. Develop an asphalt mixture JMF, then incorporate the WMA Technology additive, modifier, or process into that JMF during production. Create an asphalt JMF cover sheet (Form TR-448A) for approval containing the WMA Technology used, additive dosage rate or percent water added for foaming, material code, and the TSR data from the moisture susceptibility testing. Submit a copy of each completed JMF, signed by a certified Asphalt Level 2 plant technician, to the DME/DMM at least 3 weeks before the planned start of mixture production. Include a list of all material sources and the asphalt mixture producer in the JMF. Provide the calibration factors (C ƒ and 200 Cƒ) according to PTM No. 757 with the JMF. Do not start mixture production until after the DME/DMM reviews the JMF.

TABLE 1 Mix Design Requirements for Asphalt Rich Base Courses Volumetric Mix Design Property 25 mm NMAS Design Gyrations (Ndesign) for All Ranges of Design ESALs 50 Design Air Voids (Va) for All Specified Ranges of Design ESALs (Percent) 2.5 Voids in Mineral Aggregate (VMA) Minimum for All Specified Design ESALs and Production QC Samples (Percent) 13.0 Voids Filled with Asphalt (VFA) for All Ranges of Design ESALs (Percent) 80 – 85

314.3CONSTRUCTION—Section 4 13.3 as specified for s tandard construction and with additions and

modifications as follows:

Do not place ARBC on prepared surfaces that are wet or if the temperature of the air or the prepared surface is 35F or lower. If work is halted because of weather conditions, the Representative may allow the Contractor to place limited quantities of ARBC that are enroute to the project.

1.b Spreading and Finishing. Add the following: Place the indicated compacted depth of ARBC in one layer not less than 3 inches or more than 6 inches.

Accept ARBC by Optimum-Rolling Pattern as specified in Section 413.3(j)3.

The pavement is defective if irregularities are more than 1/4-inch.

Control the loose depth of each layer to construct the ARBC to the compacted depth indicated and within the specified tolerance. In the presence of the Inspector, drill full -depth cores at one random location selected by the Inspector according to PTM No. 1 in each 3,000 square yards of completed ARBC and at other locations the Inspector suspects are deficient. The Inspector will measure the depth of the full -depth cores according to PTM No. 737. Pavement deficient in depth by 1/2 inch or more and that cannot be satisfactorily corrected is defective. After the Inspector completes depth measurements, backfill, compact, and seal core holes with the mixture used to construct the course. Immediately start correcting courses or pavement that are deficient in depth at the core location and proceed longitudinally and transversely until the depth is less than 1/2 inch deficient of the design depth.

314.4MEASUREMENT AND PAYMENT—Section 413.4(a), with modifications as follows:

1.f Superpave Asphalt Mixture Design, Asphalt Rich Base Course. Square Yard or Ton