Evaluation of New Generation of Gap Graded Asphalt Rubber Mixtures

摘要

Based on the research and application of asphalt rubber in past few years, a new type of asphalt rubber gap graded mix, named ARAC13S, was developed and used in many projects. In this paper, AR-AC13S was compared with SMA-13 and AC-13C by a series of tests in laboratory, including wheel track tests, dynamic modulus, beam bending test, TSRST tests etc. Finally, conclusion was drawn: (1) ARAC13S had similar resistance to rutting deformation as SMA-13 at high temperature;(2)ln dynamic modulus test, gap gradation mixes were more sensitive to confinement level than dense gradation mixes, and AR-AC13S was more sensitive than SMA-13 ; (3) AR-AC13S had better performance in thermal cracking than conventional mixtures; (4)From the results of Marshall residual stability and TSR, AR-AC13 mix had the similar water susceptibility as SMA-13 and AC-13. (5) the fatigue life of AR AC13S was 17%, 87% higher than SMA-13, AC-13C respectively (6) AR-AR13S has excellent resistance to thermal cracking and fatigue, while it still keeps good performance in resistance to rutting and moisture sensitive.