废弃橡胶粉对水泥稳定碎石抗疲劳性能的影响

Effect of Waste Rubber Powder on Fatigue Performance of Cement Stabilized Gravel

为了消除水泥稳定碎石基层因疲劳损伤产生的裂缝,采用三分点加载方法系统研究了不同废弃橡胶粉掺量下水泥稳定碎石的疲劳性能,运用三点弯曲梁法表征了掺加废弃橡胶粉的水泥稳定碎石抗疲劳机理.结果表明:掺加10、20 kg/m^(3)废弃橡胶粉的水泥稳定碎石疲劳寿命优于基准组水泥稳定碎石;当废弃橡胶粉掺量为10、20 kg/m^(3)时水泥稳定碎石的起裂韧度是基准组的1.49、2.58倍,失稳韧度是基准组的1.30、2.21倍,断裂能也较大,抗疲劳性能显著;当废弃橡胶粉掺量为30 kg/m^(3)时,水泥稳定碎石的抗疲劳性能并没有提高,这可能与废弃橡胶粉掺量过大导致弯拉强度降低有关.

In order to eliminate fatigue crack,the fatigue performance of cement stabilized gravel with different waste rubber powder content was studied by three⁃point loading method.Fatigue mechanism of cement stabilized gravel with waste rubber powder was characterized by three⁃point bending beam method.The results show that fatigue lives of cement stabilized gravels with rubber powder content of 10,20 kg/m^(3) are better than that of reference cement stabilized gravel.Cracking toughnesses of cement stabilized gravels with rubber powder content of 10,20 kg/m^(3) are 1.49,2.58 times that of reference respectively.And instability toughnesses of cement stabilized gravels with rubber powder content of 10,20 kg/m^(3) are 1.30,2.21 times that of reference.So fatigue resistances of cement stabilized gravels with rubber powder content of 10,20 kg/m^(3) are remarkable because that its fracture energy is large.Fatigue performance of cement stabilized gravel with rubber powder content of 30 kg/m^(3) does not increase because that its bending tensile strength is low with increasing rubber powder content.