分层变模量下的沥青路面车辙预估模型

Rutting Prediction Model of Asphalt Pavement Under Layered Variable Modulus

为建立分层变模量下沥青路面车辙预估模型,修正动态模量变化引起沥青路面永久变形预估的偏差。根据沥青混合料动态模量试验和室内三轴动态蠕变试验,验证沥青混合料动态模量(|E^(*)|)与其抗高温变形能力的相关性;采用Abaqus有限元软件分析不同时间沥青路面随深度、温度的动态模量和竖向压应力变化规律,提出各亚层在不同动态模量下的竖向压应力修正因子(m);根据“亚层变形叠加”思想,运用SPSS软件回归分析,建立包含温度、沥青层厚度、竖向压应力、修正因子和荷载作用次数等因素的分层变模量沥青路面车辙预估模型。结果表明,建立的车辙预估模型可更为准确地预估沥青路面的永久变形,可将中、下面层车辙预估精度分别提高6.03%和10.34%,沥青层整体提高5.19%。

To establish the rutting prediction model of asphalt pavement under layered variable modulus,the deviation of permanent deformation prediction of asphalt pavement caused by dynamic modulus change was corrected.Based on the asphalt mixture dynamic modulus test and laboratory triaxial dynamic creep test,the correlation between the asphalt mixture dynamic modulus(| E^(*) |) and its high-temperature deformation resistance was verified.Abaqus finite element software was used to analyze the dynamic modulus and vertical compressive stress of asphalt pavement with depth and temperature at different times,and the correction factor(m) of vertical compressive stress of each sub layer under different dynamic modulus was proposed.According to the idea of 'sub layer deformation superposition',a rutting prediction model of layered variable modulus asphalt pavement was established by using SPSS software regression analysis,which included temperature,asphalt layer thickness,vertical compressive stress,correction factor,load action times and other factors.The results showed that the established rutting prediction model can more accurately predict the permanent deformation of asphalt pavement,improve the rutting prediction accuracy of middle and lower layers by 6.03% and 10.34%,respectively,and improve the overall asphalt layer by 5.19%.