NRMCA’s Killingsworth Briefs ACAA on Roller Compacted Concrete at Winter Meeting

The American Coal Ash Association (ACAA) hosted its annual winter meeting in Albuquerque, NM, earlier this month. In the morning session, more than 125 participants were presented with information on the current state of the coal market and the Anthracite Region Independent Power Producer's Association (ARIPPA) report on removing and utilizing coal refuse from current and past mining activities and returning thousands of acres of land back to its natural state and usefulness. Additionally, Martha Van Geem, principal engineer with Van Geem Consulting, spoke about the ongoing task of developing an Environmental Product Declaration (EPD) for fly ash and a representative from the Environmental Protection Agency discussed the recent positive finding for beneficial use of CCR in concrete.

In the afternoon, NRMCA Vice President, Pavement Structures, Brian Killingsworth presented on roller compacted concrete pavement; specifically about its uses, how it is produced and constructed, and how coal combustion products can be utilized to enhance the RCC mixture properties. Audience discussion after the presentation focused on the opportunities for high-volume fly ash replacement in RCC pavement applications and what the overall outlook is with RCC pavement in the future. Killingsworth shared with the group that fly ash, as a cement and fine aggregate replacement, is being used much more commonly in RCC paving mixtures in the U.S. and the future is very bright for this versatile paving mixture. In fact, over 17 million square yards of RCC pavement have been placed since the mid 1980’s in the U.S., wherein almost one-third of that quantity has been placed during the period from 2011 to 2013.