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From page 1... ... have established specifications permitting the use of WMA. This rapid growth in use of WMA use naturally raises questions about WMA pavement construction processes and the pavements' long-term durability and GUIDELINES FOR PROJECT SELECTION AND MATERIALS SAMPLING, CONDITIONING, AND TESTING IN WMA RESEARCH STUDIES This digest summarizes the results of a "Workshop to Coordinate Key WMA Research Projects" sponsored by NCHRP Project Panels 9-43, 9-47, and 9-49 in conjunction with the AASHTO Highway Subcommittee on Materials, the Federal Highway Administration, and the National Asphalt Pavement Association. Read the entire page →
From page 2... ... Answers to many of these questions are being pursued in WMA research studies informally coordinated through the FHWA's WMA Technical Working Group. For example, more than 15 state DOTs are currently sponsoring WMA research studies, and the 50 state DOTs are collectively sponsoring NCHRP projects investigating WMA mix design, the potential moisture susceptibility of WMA pavements, and whether WMA and HMA pavements provide significantly different short- and long-term performance. Read the entire page →
From page 3... ... The HMA control section must be identical to the WMA sections (including any RAP or RAS content) in all aspects but the presence of WMA, with the exception that the binder content of the control section may differ if necessary to attain identical air void contents in all sections. Read the entire page →
From page 4... ... as the extraction solvent is discouraged. TCE is known to harden recovered binders beyond the in situ level. Read the entire page →
From page 5... ... air voids analysis, (d) IDT creep compliance and strength, (e) Read the entire page →
From page 6... ... , then 2 to 2.5 hours at compaction temperature. For WMA mix design and volumetric analysis, moisture sensitivity (AASHTO T 283 and T 324) Read the entire page →
From page 7... ... For samples not at ambient temperature, note the temperature and reheat to compaction temperature, noting the time. Long-term aging (AASHTO R 30) Read the entire page →
From page 8... ... ASTM D7460 in strain control. Strong alternative: Tex-248-F, Test Procedure for Overlay Test, January 2009. Read the entire page →
From page 9... ... ASTM D7460 in strain control. Strong alternative: Tex-248-F, Test Procedure for Overlay Test, January 2009. Read the entire page →
From page 10... ... Overlay Test IDT creep compliance and strength Semi-Circular Bending Test Hamburg Test Moisture sensitivity Bond strength between layers Visual distress survey Rut depth profile In-place thickness and density Smoothness (IRI) FWD Permeability Gmb Gmm Air voids analysis Absorption (by calculation) Read the entire page →
From page 11... ... • IDT • SASW • Flow number (AMPT) • Hamburg Test • Hamburg Test • Beam Fatigue Test • Overlay Test • Overlay Test • IDT • Semi-Circular Bending Test • IDT • Semi-Circular Bending Test • Lottman Test • Hamburg Test • Lottman Test • Hamburg Test Test For 2 hrs @ WMA compaction temperature 2 hrs @ WMA compaction temperature 16 hrs @ 140°F + 2 hrs @ WMA compaction temperature + 5 days @ 85°C 2 hrs @ WMA compaction temperature 16 hrs @ 140°F + 2 hrs @ WMA compaction temperature (continued on next page) Read the entire page →
From page 12... ... For samples of mix not at ambient temperature, reheat at WMA compaction temperature and note time. Test For 2 hrs @ WMA compaction temperature 2 hrs @ WMA compaction temperature 16 hrs @ 140°F + 2 hrs @ WMA compaction temperature + 5 days @ 85°C 16 hrs @ 140°F + 2 hrs @ WMA compaction temperature Read the entire page →
From page 13... ... Note: Done before and after PAV aging. Use a DSR capable of handling stiff binders. Read the entire page →
From page 14... ... For example, an experiment design for a study of WMA fatigue cracking potential would not likely require the inclusion of methods for rutting, moisture sensitivity, or low-temperature cracking from the core set. Appendix A contains templates for documentation of field projects as referenced in Table 1. Read the entire page →
From page 34... ... Further, it has been shown that TCE solvent produces higher (i.e., stiffer) 3 and hardened2 recovered binders. Read the entire page →
From page 35... ... Transportation Research Board 500 Fifth Street, NW Washington, DC 20001 These digests are issued in order to increase awareness of research results emanating from projects in the Cooperative Research Programs (CRP) Read the entire page →

From page 1...

... have established specifications permitting the use of WMA. This rapid growth in use of WMA use naturally raises questions about WMA pavement construction processes and the pavements' long-term durability and GUIDELINES FOR PROJECT SELECTION AND MATERIALS SAMPLING, CONDITIONING, AND TESTING IN WMA RESEARCH STUDIES This digest summarizes the results of a "Workshop to Coordinate Key WMA Research Projects" sponsored by NCHRP Project Panels 9-43, 9-47, and 9-49 in conjunction with the AASHTO Highway Subcommittee on Materials, the Federal Highway Administration, and the National Asphalt Pavement Association.