沥青砂浆多次损伤自愈合性能

Multiple damage self healing properties of asphalt mortar

沥青砂浆由沥青、细骨料及填料三部分组成,对沥青混合料的性能具有重要影响。为对比分析自愈温度、自愈时间、老化程度及损伤程度对两种沥青砂浆愈合性能的影响,采用四因素三水平正交试验方法设计沥青砂浆小梁弯曲损伤愈合试验,选出最显著影响因素,进行多次间歇期的损伤自愈合试验。利用J积分理论对沥青砂浆的愈合程度进行价评,将断裂韧性Jc作为沥青砂浆损伤愈合的评价指标。试验结果表明:断裂韧性Jc能够表征沥青砂浆内部能量释放过程,可以很好的评价沥青砂浆的愈合能力;老化程度是影响沥青砂浆愈合性能的主要因素,与基质沥青砂浆相比,苯乙烯-丁二烯-苯乙烯(SBS)改性沥青砂浆在多次损伤自愈合后的愈合性能更好;随着损伤次数的增大两种沥青砂浆的愈合度都显著下降。试验结果可为沥青混合料性能研究及路面养护提供参考依据。

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 Jcwas used as an evaluation index of asphalt mortar damage healing.The test results show that fracture toughness Jccan 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.