移动荷载作用下饱和沥青路面动力响应三维有限元分析  

Analysis on Dynamic Response of Saturated Asphalt Pavement under Moving Vehicle Loads by 3D Finite Element Method

作　　者：任瑞波[1] 祁文洋[1] 李美玲[1] 

机构地区：[1]山东建筑大学土木工程学院,山东济南250101

出　　处：《公路交通科技》2011年第9期11-16,共6页Journal of Highway and Transportation Research and Development

基　　金：山东省自然科学基金项目(ZR2009FM010)

摘　　要：沥青路面结构在外界环境作用下是气、液、固三相介质体,水和荷载的耦合作用导致了沥青路面初期损坏的产生,探究其在车辆移动荷载作用下的动力响应是获知沥青路面结构行为的前提。首先,在沥青路面饱和情况下,作一级合理近似,将其视为流固两相介质。基于多孔介质理论,对于典型半刚性基层沥青路面结构建立了移动荷载作用下的三维有限元模型;而后对比分析了移动荷载作用下,饱和沥青路面和无水沥青路面三向应力、应变响应的时程变化规律以及竖向应力场的三维分布情况。结果表明:移动荷载作用下,饱和沥青路面面层内的动力响应特性与其无水状态时不同;沥青路面在饱和状态下更易产生疲劳开裂、永久变形等结构性损坏;路面设计指标中采用弯拉应变更为合理。Asphalt pavement is a kind of porous medium which consists of solid,liquid and gas phases under the action of outside environment.The coupled hydro-mechanical action leads to the initial failure of asphalt pavement.To explore the dynamic response of asphalt pavement subjected to moving vehicle loads is the premise for understanding the structure behavior of asphalt pavement.First,regarding asphalt mixture as a media consists of solid and liquid phases in level one reasonable approximation,based on the porous media theory,a 3D finite element model of typical semi-rigid base asphalt concrete pavement under moving load was developed in the assumption that the asphalt pavement is saturated.Then,the variation of 3D strain and stress as well as 3D distribution of vertical stress of pavement under saturated condition and dry condition were comparatively analysed.The result indicates that（1） the characteristics of dynamic response of asphalt pavement with moving load under saturated condition and dry condition in surface course are different;（2） it is more likely to have structure damage such as fatigue cracking and permanent deformation when asphalt pavement is under saturated condition;（3） in asphalt pavement design,it is more reasonable to use flexural-tensile strain as the index than flexural-tensile stress.

关 键 词：道路工程 沥青路面 多孔介质理论 有限元 移动荷载 

分 类 号：U416.217[交通运输工程—道路与铁道工程]