基于车辆加载试验的沥青路面动力响应分析

Analysis on Dynamic Response of Asphalt Pavement Based on Vehicle Loading Test

为获得行车荷载作用下沥青路面的实际动力响应规律,以实体工程为依托,铺筑了3种典型沥青路面结构的试验路。通过车辆加载试验,分析了车辆轴型、轴重、车速和胎压对路面结构层层底应变响应的影响规律,并通过疲劳寿命预估模型探讨了沥青路面基于动力响应的疲劳寿命。研究表明:路面结构在面层底和基层底主要呈现出拉应变状态,应变响应过程体现出黏弹性特征;路面面层底部的横向应变小于纵向应变,应变响应随车速的提高逐渐减小,而随轴重的增加显著增大;车轮胎压对路面动态应变响应有显著的影响作用,在车胎超压和轴重超载的叠加效应下,路面将处于极为不利的受力状态;车辆超载行驶是影响路面疲劳寿命的重要原因,应予以严格控制。

In order to obtain the real dynamic response regularity of asphalt pavement under vehicle load,the test road containing 3 kinds of typical asphalt pavement is paved based on a real project. According to the vehicle loading test,the effect regularities of vehicle axle type,axle load,speed and tire pressure of vehicle on the strain response at the bottom of pavement structure layer are analysed,and the fatigue life of asphalt pavement based on dynamic response is studied with the prediction model of fatigue life. The result shows that（ 1） the pavement structure at the bottom of surface course and base course are in tension strain state,and the strain response process reflects typical viscoelastic characteristics;（ 2） the lateral strain at the bottom of surface course is smaller than the longitudinal one,the strain response reduces with the increment of vehicle speed,and increases with the increment of axle load;（ 3） the tire pressure has notable influence on the dynamic strain response of pavement,and the additive effect of overload and over pressure sends pavement into an adverse condition;（ 4） overload of vehicle transport is an important factor affecting the pavement fatigue life,which should be strictly controlled.