基于加速加载试验的半刚性基层沥青路面动力响应

Dynamic Response of Semi-rigid Base Asphalt Pavement Based on Accelerated Pavement Test

为了了解移动车辆荷载作用下半刚性基层沥青路面结构动力响应规律,修筑足尺试验场,采用置入式应变传感器,检测加速加载设备在车轮荷载作用下的面层底部动力响应,研究了面层底部横向分布以及轴重和温度对路面结构动力响应的影响。结果表明:移动车轮荷载下,面层底部纵向弯拉应变呈拉压应变交变状态,荷载位置仅影响其数值大小;横向弯拉应变比较复杂,胎冠下部呈现拉应变状态,2个轮胎之间及轮胎外侧呈现压应变状态,胎肩位置呈现拉压应变交变状态;面层底部弯拉应变无法充分反映超载车辆对路面的破坏作用;温度对路面结构的动力响应影响显著,30℃、40℃和50℃下沥青路面动力响应分别为常温状态下的3倍、8.9倍和13.3倍。

In order to study the dynamic response rule of semi-rigid base asphalt pavement structure under moving load,a full-scale test ground was built,and set-in sensors were used to detect the dynamic response of accelerate loading facility at the bottom of the surface layer under wheel load,and the influences of the lateral distribution of bottom of surface layer,axle load and temperature on the dynamic response of pavement sructure were studied.Results show that the longitudinal flexural-tensile strain at bottom of surface layer presents alternating strain under moving wheel load and the load position only influences its magnitude.The lateral flexural-tensile strain presents quite complex,and it presents tensile strain at the bottom of the tire crown.It presents compressive strain at the positions of two tires middle and two tires lateral.It presents alternating strain at the bottom of the tire shoulder.The flexural-tensile strain at the bottom of the surface layer can not reflect the pavement damaging condition by the overload trucks.Temperature has significant influence on the dynamic response of the asphalt pavement structure,and the dynamic responses at 30 ℃,40 ℃ and 50 ℃ are respectively equivalent to 3 times,8.9 times and 13.3 times of dynamic response at common temperature state.