Performance of Asphalt Rubber Mixes in California

This paper addresses the experience gained in California with asphalt rubber mixes from the performance of field test sections, accelerated pavement tests and laboratory performance tests. Field and laboratory studies have evaluated the performance of asphalt rubber mixes in terms of fatigue, reflective cracking, permanent deformation and moisture sensitivity. The findings have shown that asphalt rubber mixes, when properly designed and constructed, can provide superior performance as compared to conventional dense graded mixes. A proper mix design would be based on performance testing consisting of repetitive permanent deformation testing, fatigue testing, thermal cracking testing and moisture sensitivity evaluation. Mechanistic analysis is necessary so that the structural contribution of asphalt rubber mixes can be quantified. Layer thicknesses will have to be based on fatigue testing accompanied by mechanistic analysis.