Effect of LDHs on the aging resistance of crumb rubber modified asphalt

Layer double hydroxides (LDHs), a kind of ultraviolet light resistant material, was added into the Crumb Rubber Modified Asphalt (CRMA) and its effects on the aging resistance of the CRMA were investigated in this paper. The short-term and long-term aging processes of asphalt were simulated by Thin Film Oven Test (TFOT) and ultraviolet (UV) radiation test, respectively. With Fourier Transform Infrared Spectroscopy (FTIR) measurements, it was found that LDHs can slow down the formation of carbonyl groups during the aging process. The conventional physical properties test and Dynamic Shear Rheometer (DSR) test were used to evaluate the properties of the asphalt. The results showed that the softening point increases and G* ratios of CRMA decreases significantly, the ductility and the penetration retention rate increase after ultraviolet aging due to the introduction of LDHs. Besides, the results of both creep and relaxation test implied that the LDHs modified CRMA binder has a better UV aging resistance. (C) 2013 Elsevier Ltd. All rights reserved.