USE, AVAILABILITY AND COST-EFFECTIVENESS OF ASPHALT RUBBER IN TEXAS. FINAL REPORT

A study was conducted for the Texas State Department of Highways and Public Transportation (SDHPT) by the Texas Transportation Institute to address the following issues: (1) the current extent of usage of asphalt rubber by the Department; (2) the availability of crumb rubber produced from scrap tires and the availability of asphalt rubber in the State of Texas; and (3) the cost-effectiveness of asphalt rubber as compared to conventional paving materials based on existing information and on the experience of Department personnel. Published information was canvassed, phone interviews with knowledgeable Department personnel were conducted, and existing laboratory information was evaluated. The Texas SDHPT currently utilizes asphalt rubber in four different applications. They are, in descending order of their volume of asphalt rubber consumption: (1) chip seal or stress absorbing membrane (SAM) construction, (2) stress absorbing membrane interlayer (SAMI) construction, (3) crack and/or joint sealing, and (4) hot-mix asphalt concrete pavement construction (on a very limited experimental basis). These applications of asphalt rubber are described in detail in this report. Appendix A contains descriptions of current and proposed innovative uses for scrap tires other than in asphalt pavements which could potentially consume all of the scrap tires produced in the United States.