Multiple damage self healing properties of asphalt mortar

Asphalt mortar consists of three parts asphalt, fine aggregate and filler, which has important influence on the performance of asphalt mixture. Four factors and three levels orthogonal test were used to test the damage of the asphalt mortar. The influences of self-healing temperature, self-healing time, aging degree and damage degree on the healing properties of two kinds of asphalt mortar were compared and analyzed, and the most significant influence level was selected to undergo multiple intermittent damage self-healing tests. J-integral theory was used to evaluate the degree of healing of asphalt mortar, and fracture toughness J_c was used as an evaluation index of asphalt mortar damage healing. The test results show that fracture toughness J_c can well describe the internal energy release process of asphalt mortar, and can be used as the healing index of asphalt mortar. Aging degree is the main factor affecting the healing property of two kinds of asphalt mortar. Compared with the matrix asphalt mortar, the styreneic block copolymer(SBS) modified asphalt mortar has better healing performance after repeated damage and self-healing. With the increase of damage times, healing degree of the two kinds of asphalt mortar decreases significantly. The test results can provide reference for asphalt mixture performance research and pavement maintenance.