Abstract: In order to analyze the performance of tire rubber ash(TRA)modified asphalt, the TRA was prepared by high temperature thermal decomposition and two kinds of matrix asphalt with different ash content(0%-5.0%) were used to prepare the TRA modified asphalt in this experiment.The three index of asphalt,dynamic shear rheometer (DSR), penetration index, viscosity, elastic recovery, thin film oven test (TFOT) and standard test method for separation were carried out to study the high temperature characteristics, low temperature performance, temperature sensitivity, viscosity temperature properties, elastic recovery, aging properties and storage stability of TRA modified asphalt.And scanning electron microscopy and fluorescence microscopy were applied to analyze the microstructure of TRA and the modification effect of the modified asphalt.The results show that the high temperature performance of asphalt with TRA can be significantly improved, which can also reduce the temperature sensitivity and improve the viscosity temperature performance;when the content of TRA is lower than 3.0%, the elastic recovery of asphalt is improved significantly, and the TRA modified asphalt has no significant effect on the low temperature performance, aging properties and storage stability.Therefore, the advisable addition of TRA is 3.0%.Meanwhile, the microscopic test show that the TRA particles are irregular honeycomb structure with sticky pores, which can adsorb asphalt and evenly distribute in the asphalt.

Key words: tire rubber ash (TRA);modified asphalt;microstructure