汽车荷载作用下沥青路面公路动力响应数值模拟

Numerical analysis of bitumen-surface highway dynamic response under vehicle loads

运用ANSYS软件建立沥青路面与路基三维动力分析模型,采用双频率正弦波动荷载模拟车辆动荷载,分析了三轴六轮组的东风重型货车在车速为72 km/h时,满载和超载80%两种工况下路面和路基动力响应。计算结果表明:轮距中心左右各2 m的范围内,面层结构横向应力分布呈双峰状,轮迹处最大,然后向两边衰减;且随着深度增加,应力逐渐由压应力转化为拉应力,拉应力在面层下56 cm处达到最大;竖向动应力在路基内随着深度的增加逐渐减小,沿横向在路基表面呈马鞍状分布,且随着深度增加逐渐变为单峰分布;满载及超载80%时动荷载影响深度分别为2.2m和2.6 m,影响宽度分别为4m和6.5 m。

3 d dynamic analysis models of asphalt pavement and subgrade were established by finite element software ANSYS. Vehicle dynamic loads were simulated by dual frequency sine wave. The dynamic response of pavement and subgrade were analyzed under the action of Dongfong truck when the speed is 72 km/h with full load and over load 80%. The calculated results show that within the scope of each 2 m around tread center, transverse stress distribution of the surface layer structure is bimodal shape. The maximum appears in place of wheel track and then attenuates toward both sides. With the increase of the depth, the stress changes gradually from the compressive stress into tensile stress, and the maximum tensile stress appears 56 em under surface layer. Vertical dynamic stress decreases gradually with the increase of the depth in the subgrade. Vertical dynamic stress shows saddle - shaped distribution along the horizontal surface of the subgrade, and with increase of the depth, it increasingly becomes unimodal distribution. The influence depth of the dynamic loads with the action of full load and overload of 80% are 2.2 m and 2.6 m, the width are 4 m and 6.5 m.