NMSU Las Cruces Study Finds Old Tires Can Become New Roads
Las Cruces – A new study by the New Mexico State University (NMSU) Civil Engineering Department finds roadways paved with asphalt concrete containing crumb rubber (produced from recycled tires), perform as well as or better than roads paved with conventional paving materials.
Those results could lead to a substantial win-win for the Land of Enchantment, by not only improving the state's roads, but also finding a viable beneficial use for the hundreds of thousands of scrap tires that are illegally dumped throughout the State.
Expectations from rubberized asphalt roads include quieter traffic noise, smoother pavement, longer performance life and ability to withstand higher air temperatures. Four rubberized asphalt projects completed this year in the NM Department of Transportation Districts 1 and 2 show those Districts' willingness and interest to use the product, based on successful experience of other states. Leaders in the utilization of rubberized asphalt include California, Arizona, Texas and Florida, providing twenty years of data and comparisons to regular asphalt paving projects. Although a higher cost to initially lay the rubberized pavement has been a hindrance to new projects, one NMDOT District 1 paving project showed only a $1/ton price premium over traditional materials. The new projects are located along Highway 54, I-10 and I-25.
"The use of asphalt rubber products in pavements in New Mexico should be based on documented performance, particular project conditions or requirements, and life cycle analyses," explained lead NMSU researcher Dr. Paola Bandini. She also noted that several rubberized asphalt projects have been completed on municipal and private property paving projects.
The study commissioned by the New Mexico Environment Department (NMED) Solid Waste Bureau and the South Central Solid Waste Authority (SCSWA) evaluated road performance of rubberized asphalt pavements both in New Mexico and other states. This type of paving uses old, shredded tires to create the material called crumb rubber. The crumb rubber is then mixed into asphalt and applied as a component of the paving process.
Solid waste managers around the state struggle to keep tires out of arroyos and would prefer to keep them out of landfills due to their size and shape. Unlike scrap metal and other recyclables, which hold a value when recycled, communities must pay to have their tires properly disposed. Finding viable uses for tires, preferably with a market value, is ideal - one of which is turning tires into pavement.
Patrick Peck, the South Central Solid Waste Authority Director in Las Cruces explains, "Right now we landfill more than 10,000 tires each year and clean up thousands from illegal dump sites; I'd much prefer to have those tires recycled and put to good use."
The report can be found online at http://www.nmenv.state.nm.us/swb/tires.htm.