随机荷载作用下沥青路面动力响应研究

Dynamic response of asphalt pavement under random load

为了分析车辆行驶过程中因路面不平产生的随机荷载引起沥青路面的动力响应,采用脉冲响应法模拟随机荷载下的路面响应,并用2自由度1/4车辆模型模拟车辆荷载,建立了三维有限元模型评估移动荷载激励下的不同速度、不同深度的沥青路面动力响应。结果表明:从不同速度的移动荷载作用下的路面应力、位移随深度的变化规律看,最大竖向应力、横向应力、位移均出现在面层表面,且随着深度的增加,应力、位移都逐渐减小。当车辆的行驶速度在10~20 m/s时,对路面的冲击较大;随着速度的提高,路面的最大竖向位移和最大竖向应力迅速减小,当速度增加到30 m/s时,路面的竖向位移和竖向应力均达到最小值,此后开始逐渐增加。

In order to analyze the dynamic response of asphalt pavement caused by random loads generated by uneven road surfaces during vehicle driving,the pulse response method was used to simulate the road response under random loads,and a two degree of freedom quarter vehicle model was used to simulate vehicle loads.A three-dimensional finite element model was established to evaluate the dynamic response of asphalt pavement at different speeds and depths under moving load excitation.The results show that,from the variation of road stress and displacement with depth under the action of moving loads at different speeds,the maximum vertical stress,lateral stress,and displacement all appear on the surface of the surface layer,and as the depth increases,the stress and displacement gradually decrease.When the driving speed of the vehicle is between 10 m/s and 20 m/s,the impact on the road surface is significant.With the continuous increase of speed,the maximum vertical displacement and maximum vertical stress of the road surface rapidly decrease.When the speed increases to 30 m/s,the vertical displacement and vertical stress of the road reach their minimum values,and then gradually increase.