不同行车荷载下的沥青路面应变响应试验研究

Test and Research on Strain Response of Asphalt Pavement under Different Vehicle Load

针对半刚性路面(S1)、倒装式路面(S2)和组合式路面(S3)3类典型沥青路面结构,以实体工程为依托,开展不同行车荷载条件下的路面动力响应现场测试,揭示了车辆荷载大小及行车速度对于沥青路面动态应变响应的影响规律。研究结果表明:车辆动态荷载所引起的层底应变响应明显小于静态轴载作用;面层层底应变随车速提高逐渐减小,轴载水平越高,减小速率越快;面层层底应变随轴重增加逐渐增大,且在动载模式下轴重对于应变响应的影响作用较静态荷载更为显著;面层底纵向应变大于横向应变;基层层底应变随轴重增加逐渐增大,而受车速变化的影响作用较小;轴载水平越高,胎压增加对应变响应的影响作用越显著;在车轮动态荷载作用下,胎压对面层底部应变响应的影响作用明显大于静态荷载。

Regarding three types of typical asphalt pavement such as asphalt pavement with semi-rigid base （S1）, inverted asphalt pavement structure （S2）, and compound asphalt pavement （S3）, a field measurement test based on a real project is conducted to obtain dynamic response of pavement under different vehicle loads. The influence of axle load and speed are also evaluated. The results show that for the dynamic strain at the bottom of surface course, the strain caused by dynamic load is obviously less than the strain caused by the static load. The strain response reduces with the increment of vehicle speed, and the higher the load level is, the higher the decrease rate is. The strain increases with the increment of the axle load, and the load influence under the dynamic load is more significant than the static load. The lateral strain at the bottom of surface course is smaller than the longitudinal one. The strain at the bottom of base course increases with the increment of axle load, but the speed influence on the strain response is not obvious. The higher the axle load level, the more significant the influence of tire pressure on the strain response. The influence of tire pressure on strain response which is under the dynamic load mode is more obvious than the static load mode.