Description
The Arizona Department of Transportation (ADOT) has used Asphalt Rubber (AR) in hot mix asphalt since 1988. The primary purpose for using AR is to reduce reflective cracking in Hot Mix Asphalt (HMA) rehabilitation overlays. Currently, there are no standards or laboratory test data in Arizona to support the knowledge area on the usceptibility of asphalt rubber mixtures to moisture damage. The AASHTO T 283 is widely accepted as a test to predict moisture damage in asphalt concrete pavements.
This study was an investigation to identify whether the AASHTO T 283 Modified Lottman moisture susceptibility test can be successfully applied to assess moisture damage of the AR mixtures used in Arizona. The research scope of work included conducting laboratory testing program on AR and conventional HMA mixes using AASHTO T 283 to determine the indirect tensile strength and Tensile Strength Ration (TSR). The test results are discussed along with
recommendations on modified test procedures and acceptance limits for Asphalt Rubber Gap and Open graded mixtures.