Every January, thousands of transportation professionals flock to the nation's capital for the Transportation Research Board (TRB) Annual Meeting. The 96th Annual Meeting was held January 8-12 at the Walter E. Washington Convention Center in Washington, DC. Over 800 sessions and workshops are compressed into the five-day meeting and address relevant topics of interest for policy makers, researchers, industry representatives, etc.
Session #174 (pictured right), Asphalt Mixture Volumetrics: Applying Reasonableness and Avoiding Pitfalls, was our favorite of this year's meeting. The group addressed the basics of asphalt mixture volumetrics and the importance of grasping the concepts. Additionally, the group also mentioned how the industry is transitioning towards performance testing and how volumetrics alone cannot predict pavement performance. The panel and attendees of the session consisted of industry experts from all over the world.
This year SCAPA's research work with Advanced Materials Services, LLC was presented in front of pavement design professionals at the meeting. Session #219, Backcalculation and Evaluation of Pavement Sections, featured presentations from pavement design experts across the country. Dr. Brian Prowell of Advanced Materials Services, LLC worked with SCAPA on utilizing moduli data of SC's asphalt base mixes and backcalculating those values to estimate a structural coefficient. SCDOT currently utilizes AASHTO's 1972 Pavement Design methodology and localized structural coefficients from a 1971 Clemson University study. SCDOT's Coefficients of Relative Strength assigns a 0.34 structural coefficient to asphalt base mixtures (0.44 is assigned to surface and intermediate mixes). Dr. Prowell's findings show that SC base mixes can be optimally designed with a higher structural coefficient, which would yield thinner pavement sections. As a result, this potentially saves SC taxpayers lots of money. SCAPA plans to release the research findings in the Resources section of scasphalt.org in the coming months.