Description
Till now, only dry process is used to manufacture asphalt rubber (AR) in highway in China. This paper describes the production of asphalt rubber with wet process and the application of asphalt rubber for concrete pavement overlays. This paper presents: (1) selection of crumb rubber and base asphalt; (2)producing parameter tests that affect the
properties of asphalt rubber; (3) evaluation of performances of asphalt rubber Stress Absorbing Membrane Interlay (AR-SAMI);(4)evaluation of different design methods of gap graded asphalt rubber mixture (5)usage of asphalt rubber in test sections. After a series of tests, some conclusions were drawn from this research. Asphalt rubber using truck tire crumb rubber had better performances than that using car tire crumb rubber. Using #20 mesh size
crumb rubber could give better asphalt rubber than #40 mesh and #60 mesh crumb rubber. As for base asphalt, asphalt rubber using penetration 70 base asphalt had better high temperature performance than that using penetration 90 base asphalt, but its low temperature performance and fatigue resistance were not as good as asphalt rubber using penetration 90 asphalt. AR-SAMI had good fatigue and shear resistance. Gap graded asphalt rubber mix designed using Superpave Gyratory Compactor(SGC) method had better rutting and low temperature cracking resistance than that using Marshall method.
