面层与基层层间摩擦系数对应力强度因子影响的研究

开裂为沥青混凝土路面中存在的主要问题。基于线弹性断裂力学理论,采用ABAQUS软件中的平面应变单元法,分别分析了变温作用下裂缝的长度、面层与基层层间摩擦系数态对含表面裂缝和含反射沥青混凝土路面的应力强度因子分布规律的影响。得出了含表面裂缝和反射裂缝路面体的应力强度因子均随着裂缝长度的增加逐渐增大。表面裂缝裂尖位于面层中时,应力强度因子随着摩擦系数的增加而逐渐减小;裂尖位于基层中时,应力强度因子随着摩擦系数的增加而逐渐增大。反射裂缝裂尖位于基层中时,应力强度因子随着摩擦系数的增加而减小;反射裂缝裂尖位于面层中且长度小于某一值时,应力强度因子随着摩擦系数的增加而增大;反射裂缝裂尖位于面层中且裂缝长度大于某一值时,应力强度因子随着摩擦系数的增加而减小。

STUDY ON STRESS INTENSITY FACTOR AFFECTED BY FRICTION COEFFICIENT BETWEEN SURFACE LAYER AND SUBBASE

Cracking is a major problem in the asphalt concrete pavement. Based on the linear fracture mechanics, the distribution discipline of the stress intensity factor (SIF) under the changed temperature is studied by the plane strain FEM of ABAQUS software when the surface cracks or the reflective cracks exist in the asphalt pavement on the semi-rigid base. It is obtained that the SIF increases with the length of the surface crack or the reflective crack enlarging in the asphalt pavement. The SIF decreases with the friction coefficient rising when the surface crack tip lies in the surface layer and increases with the friction coefficient rising when the surface crack tip lies in the base. For the asphalt pavement with reflective crack,the SIF decreases with the friction coefficient rising when the reflective crack tip lies in the base. The SIF increases with the friction coefficient rising when the reflective crack tip lies in the base and the reflective crack length is less than a certain value. The SIF decreases with the friction coefficient rising when the surface crack tip lies in the base and the reflective crack length is more than a certain value.