Better Roads

RoadScience by Tom Kuennen, Contributing Editor 4 March 2014 Better Roads T he latest National Asphalt Pavement Associa- tion (NAPA)/Federal Highway Administration (FHWA) survey of asphalt producers' use of recycled materials and warm-mix asphalt fi nd that nearly a quarter of all asphalt produced during the 2012 construction season was produced using warm-mix asphalt technologies. The survey, conducted by NAPA under contract to FHWA, found a total of 86.7 million tons of WMA were produced in 2012, a 26-percent increase since 2011 and a 416-percent increase in the use of warm mix since the survey was fi rst conducted in 2009. The full survey may be downloaded at asphaltpavement.org/recycling. The interest in WMA is refl ected by the large number of peer-reviewed technical papers on WMA presented at the 93rd annual meeting of the Transportation Research Board (TRB) meeting in Washington, D.C., in January. The annual event was held Jan. 12-16 and kicks off the year for the surface transportation community. Nearly 12,000 transportation professionals came to Washington from around the world for the 2014 event. The TRB Annual Meeting program covered all transporta- tion modes, with more than 4,500 presentations in nearly 800 sessions and workshops addressing topics of interest to stakeholders in government, industry and academia. For nearly 60 years, TRB has been held among a cluster of hotels along Connecticut Avenue near Woodley Park and the National Zoo, but in 2015 it will move to bigger digs at the Walter E. Washington, D.C., Convention Center. Following are summaries of some of the technical papers at TRB of interest to the readers of Better Roads. For more infor- mation, visit trb.org. The incursion of warm-mix asphalt (WMA) into the nation's bituminous pavements continues unabated. Special Repor t from TRB 2014: Special Repor t from TRB 2014: Warm-Mix Asphalt Warm-Mix Asphalt Porous asphalt pavement is similar to open-graded friction courses (OGFC), with the same problem of drain- down, but is meant for static loads and environmentally sustainable stormwater drainage. Here, mix for the pa- rade ground at U.S. Marine Corps Recruit Depot at Parris Island, S.C., contains warm-mix additive instead of fi bers. Photo courtesy of Tom Kuennen

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• ROAD SCIENCE: Special Report from TRB meeting: The latest National Asphalt Pavement Association (NAPA)/Federal Highway Administration (FHWA) survey of asphalt producers' use of recycled materials and warm-mix asphalt find nearly a quarter of all asphalt p
• APPLICATIONS & INNOVATIONS: Innovations for Snowfighters: From the havoc severe winter weather has wrecked this year to sustainability in action and lessons learned from other agencies, here's a look at the latest in snow and ice control and a sneak peek
• HIGHWAY CONTRACTOR: The Magic of Rubberized Asphalt: As prices for asphalt cement and polymer have shot up dramatically, agencies and contractors are looking for ways to hold the line on the cost of asphalt pavements.
• Transportation Talk: Are we able to stop a painful transportation revenue situation before funds run out for HTF?
• In Court: Why it's important for contractors to understand the distinctions between public works versus private works improvements
• The Last Word: The sage continues with "Booth babes and the S.T.E.A.M. professions, " plus how "eye candy" can harm credibility.
• New Road Products