不同形式荷载下沥青混凝土路面结构力学响应的对比分析

Comparative Analysis of Mechanical Response of Asphalt Concrete Pavement to Different Loads

在分析车辆荷载作用下路面结构响应时,车辆荷载通常被简化为静止、振动和匀速移动3类形式。为了准确把握荷载不同简化形式下路面结构响应的差异,根据柔性路面的典型结构形式,建立了路面结构的离散元模型;采用离散元颗粒流软件,分别模拟了静止、振动和移动荷载对路面结构的作用,并对比分析了不同荷载形式下路面结构的力学响应。结果表明,静止、振动荷载只能反映移动荷载作用于路面结构后最大响应,亦即移动荷载越过路面结构某位置的瞬间,静止荷载响应与振动和移动荷载响应的峰值相当;静止、振动荷载不能反映移动荷载对路面结构引起的拉、压交替响应,以及车辆移动引起的路面结构内水平剪应力不同方向的两次作用。

Wheel loads in present pavement analysis systems are commonly simplified as three forms, namely static load, vibrating load and moving load with a constant speed. In order to understand the diffe rence of pavement response subject to the three simplified loadings, the discrete element model of pave-ment structure is constructed according to a typical flexible pavement. The effects of loading on pavement structure are simulated using the discrete element method. Thereafter, comparisons of pavement response subject to the three different loading are performed. Results show that only the maximum response to moving load can be reflected by static and vibration loading. The alternation of tensile and compressive response and double-action of the horizontal shearing stress cannot be simulated by static and vibration loading.