纤维沥青路面抗裂性能机理分析

Mechanical Analysis of the Crack-Resisting Performance of Asphalt Pavement with Fibre

针对沥青路面反射裂纹病害较为普遍的现状,以漯河市旧路改造项目,通过室内低温抗裂实验,结合平面应变有限单元法,验证了纤维材料对沥青路面抑制反射裂纹扩展的有效性。基于动力学,结合粘弹性力学理论,根据室内试验得出纤维沥青路面的本构关系,以动态应力强度因子为表征参量,探讨了纤维沥青路面在单周期垂直载荷和水平载荷共同作用下的动力特性,分析了车辆制动对纤维沥青路面工作性状的影响,研究了阻尼比,回弹模量的变化对动态应力强度因子影响。数值结果表明:掺加纤维后对沥青路面的工作性能有了较大改善,动态应力强度因子明显降低,对抑制沥青路面反射裂纹扩展起到了显著的作用。

According to the situation that the widespread diseases of asphalt pavement with reflective crack, the effectiveness of preventing the spread of the reflective crack of asphalt pavement is proved through the field crack-resisting experiment at low temperature and the finite element analysis of the old pavement reconstruction project in Luohe city. Based on the theory of dynamics and viscoelastic fracture mechanics, the constitutive relationship of asphalt pavement with fiber is developed through the field experiment, the performance of dynamic stress intensity factor under the single cyclic vertical load and lateral load is discussed, the fatigue mechanism of asphalt pavement with fiber under vehicle braking is analyzed and the general behavior of the pavement is illustrated under different material damping ratios and resilient elastic modulus. The calculated results show that the performance of the pavement is obviously improved; dynamic stress intensity factor is significantly decreased and the fiber effectively prevents the spread of the reflective crack of asphalt pavement.