高速公路路基动力响应现场试验与数值分析

The field test and numerical analysis of expressway subgrade dynamic response

基于长沙绕城高速公路路基的动力响应现场试验,让车辆荷载直接作用于路基上,运用光纤光栅元件对路基下多个测点进行测试.根据现场试验结果,结合数值计算模拟软件,分析了路基动应力随路基深度的衰减关系,认为标准轴载的动应力影响深度为3m左右.与此同时,还得到了不同车辆荷载在不同行驶速度的动应力的变化规律.创新性地提出了车辆荷载的正弦函数的修正模型.

In the field test of Changsha ring expressway subgrade dynamic response,let vehicle load act directly on the roadbed and use the fiber grating element to test the multiple measuring points under the subgrade.According to the results of field test,combined with numerical simulation software and analyzing the attenuation relationship between subgrade dynamic stress and the subgrade depth,the influence depth of the dynamic stress of the standard axle load is about 3m.At the same time,we also obtain a variation of the dynamic stress of different vehicle load in the different speed.Furthermore,a correction model of sine function of vehicle load is put forward innovatively.