Asphalt Pavement Magazine - March/April 2015 - (Page 9)

President's Perspective Setting the Record Straight on Asphalt Recycling Reclaimed asphalt pavement (RAP) is a hot topic. It offers great potential and has wide-ranging implications. In January 2015, Asphalt Pavement magazine sat down with NAPA President Mike Acott to talk about RAP and its future. This is an excerpt from that conversation. Q: What are the primary benefits of asphalt pavement recycling? A: Well, the primary benefit of using RAP is that it makes our product affordable for our customer, despite increases in binder, aggregate, and energy costs. In 2013, the estimated savings on binder alone was $2.04 billion. There are also significant environmental benefits through a savings of landfill space and a major reduction in greenhouse gas emissions. We estimate 8.9 million metric tonnes of CO2 equivalents were saved in 2013 by using RAP. The benefits are so great we expect RAP will continue as a major competitive advantage. The asphalt pavement industry is operating in an environment where contractors and their customers include sustainability in their mission statements and have specific sustainability goals. In the future, we expect asphalt producers will be asked to provide sustainability metrics for their asphalt mixtures and that this will be an input in a life-cycle assessment. Q: What distinguishes asphalt recycling from other recycled paving materials? A: Cold milling, which is often part of the rehabilitation process, provides a ready supply of crushed RAP. Other paving materials do not have this continuous pipeline of easily processed reclaimed material. The asphalt cement in old pavement has a unique quality. It can be rejuvenated and reused as if it were virgin binder. The ability of our industry to reuse both the aggregate and the binder in the RAP is a distinct competitive advantage over other pavement materials. Q: Exactly how much RAP is being used? A: The average percentage of RAP used in asphalt mixtures has grown over the last few years. In 2008, we estimated the average was 12 percent. According to a NAPA/FHWA survey in 2009, 56 million tons of RAP were used, averaging 16.2 percent in an asphalt mix. For 2013, 67.8 million tons of RAP were used, averaging 20 percent. Mike Acott, NAPA President Q: Is the reported 20 percent average RAP content level a reasonable metric for where our industry is today in terms of RAP use? A: It's an average. I'm not sure it provides a complete picture of our industry's RAP use. The 20 percent is an average across the total U.S. tons, an average across all mix types, markets, and regions. There is no distinction between the public and private sector markets. The residential/commercial market, which has had a higher RAP usage than public funded highways, was especially impacted by the downturn in the economy. In some of the rural areas, RAP may be in short supply; contractors may use all their RAP by including lower percentages across all tons. In some of the high population urban areas where there may be excess RAP, there is an economic and sustainability incentive to increase RAP use. There are several lead states such as Virginia, Florida, Ohio, and Michigan that have been using RAP for close to 40 years; for these states, the average RAP use is in the 25-32 percent range. Their mix design and operating practices are well developed with a high level of confidence on the performance of the mix. In 2009, at a time of high energy prices, NAPA set a goal of doubling RAP use from a 12 percent average RAP content to 25 percent by 2014. For some states, we are already there; for others, we will have to wait and see what the results are from the data gathered in 2015 about the 2014 construction season. continued on page 10 Asphalt Pavement Magazine - March/April 2015 * 9

Table of Contents for the Digital Edition of Asphalt Pavement Magazine - March/April 2015

President’s Perspective Setting the Record Straight on Asphalt Recycling
Industry News TCC Study Finds Transportation Infrastructure Investment Benefits All Sectors of Economy, Silent Auction to Benefit NAPA Care, NAPA Launches Diamond Terminal Commendation, 2015 AASHTO & APTA Bottom Line Report, 2015 Quality in Construction Awards Program Opens for Nominations April 1
Successful Pavement Preservation with Thin Asphalt Concrete Overlays Excerpts from NCHRP Synthesis 464: Thin Asphalt Concrete Overlays
Improving Life-cycle Performance with Pavement Interlayers The right pavement interlayer can mitigate distress and promote long-term pavement performance
NCAT Pavement Preservation Experiment Set to Expand in 2015 Lee Road 159 offers valuable pavement preservation lessons to build on
A Smooth, Rehabilitated Ride in Georgia GDOT’s formula for high quality pavement preservation
Industry Events
Index of Advertisers/

Asphalt Pavement Magazine - March/April 2015