论文部分内容阅读
为探究动态荷载作用下沥青路面的剪应力响应特征,应用ABAQUS建立半刚性路面(S1)、倒装式路面(S2)、组合式路面(S3)的动力有限元分析模型,针对3类典型沥青路面的剪应力空间分布特性,动、静剪应力差异以及路面结构和车辆荷载参数对剪应力的影响规律等方面开展数值模拟分析。研究结果表明:沿路面深度方向,剪应力最大值位于中面层顶面位置(40 mm深度处);剪应力在水平面的分布主要集中在车轮荷载作用区域,最大值位于轮印边缘位置处;S2的剪应力最大,S1与S3的剪应力较为接近,S3略大于S1;相比于静态荷载,动荷载作用下的剪应力更大,二者的差异性随轴重水平提高逐渐增大;剪应力随基层模量增加而减小,随面层模量的增大而增大,随基层厚度增加逐渐减小;随着车速和轴重的提高,路面剪应力均逐渐增大;剪应力随轴距增加呈先增大后减小的趋势,在轴距取1.1 m时,剪应力出现最大值;随着行车加速度的增加,路面剪应力基本呈线性关系增大,轴重与车速的提高,均会增大沥青路面在车辆制动过程中的剪应力。
In order to investigate the shear stress response of asphalt pavement under dynamic loading, dynamic finite element analysis model of semi-rigid pavement (S1), flip-mounted pavement (S2) and combined pavement (S3) The spatial distribution characteristics of the pavement shear stress, dynamic and static shear stress differences and the influence of pavement structure and vehicle load parameters on the shear stress are analyzed numerically. The results show that the maximum shear stress is located at the top surface of the middle layer (depth of 40 mm) along the depth of the pavement. The distribution of shear stress in the horizontal plane is mainly concentrated in the wheel load area and the maximum is located at the edge of the wheel mark. The shear stress of S2 is the largest, the shear stress of S1 and S3 are close, and S3 is slightly larger than S1. Compared with static load, the shear stress under dynamic load is larger, and the difference between them increases with the increase of axle load. The shear stress decreases with the increase of the base modulus, increases with the increase of the surface modulus and decreases with the increase of the base thickness. With the increase of vehicle speed and axle load, the pavement shear stress increases gradually. The shear stress With the increase of the wheelbase, the shear stress first increases and then decreases. When the wheelbase is taken as 1.1 m, the maximum shear stress appears. With the increase of the vehicle acceleration, the linear relationship of the road surface shear stress increases substantially. The axial load and the vehicle speed Improve, will increase the asphalt pavement in the vehicle braking process of shear stress.