离散元法的沥青路面车-路动力学响应分析  

Dynamic Response Analysis of Vehicle-load on Asphalt Pavement Based on Discrete Element Method

作　　者：严战友 王朝辉[3] 陈恩利 司春棣[2] 王向平[4] YAN Zhan-you;WANG Zhao-hui;CHEN En-li;SI Chun-di;WANG Xiang-ping(School of Civil Engineering, Shijiazhuang Tiedao University, Shijiazhuang 050043, Hebei, China;Key Laboratory of Traffic Safety and Control in Hebei Province, Shijiazhuang Tiedao University, Shijiazhuang 050043, Hebei, China;Tianjin Rail Transit Operation Group Co., Ltd., Tianjin 300000, China;Hebei Qugang Expressway Development Co., Ltd., Dingzhou 073000, Hebei, China)

机构地区：[1]石家庄铁道大学土木工程学院,河北石家庄050043 [2]石家庄铁道大学交通安全与控制河北省重点实验室,河北石家庄050043 [3]天津轨道交通运营集团有限公司,天津300000 [4]河北曲港高速公路开发有限公司,河北定州073000

出　　处：《中国公路学报》2019年第9期51-60,79,共11页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(111172183);河北曲港高速公路开发有限公司科技计划项目(QG2018-07);中央引导地方科技发展专项(18242219G)

摘　　要：为了分析车辆荷载作用下沥青路面结构的细观状态力学响应,建立了二自由度1/4车辆模型与多层路基路面耦合离散元模型,通过各结构层单轴压缩应力-应变试验与相同工况试验数据比较,经迭代运算得到路面离散元模型各结构层细观参数,应用试验得到的沥青路面细观参数建立多层路基路面模型,在离散元模型的上表面设定一定不平度,在一定速度作用下,1/4车辆模型在路基路面离散元模型上表面匀速移动,从而求解车辆动荷载作用下沥青路面各结构位移、应力等细观受力状态.进而改变1/4车辆模型的车体悬架刚度、悬架阻尼系数、轮胎刚度,轮胎阻尼系数,从而获得在改变车辆参数作用下沥青路面内部的应力变化规律.研究结果表明:基于离散元理论不但可以求得沥青路面在车-路相互作用下各层的应力与变形,而且还可以求得沥青路面各结构层颗粒流的变化趋势,在车辆移动荷载作用下,随着路基路面深度增加,各结构层颗粒流竖直方向动态位移与应力响应依次减少,其中上基层颗粒流动位移比上面层颗粒流动位移减少25%,下面层颗粒流竖向应力约为上面层颗粒流竖向应力的50%,水平方向上颗粒流既有压应力又有拉应力,变化比较复杂,上面层颗粒流水平方向主要承受压应力,其余结构层主要承受拉应力;增加轮胎与悬架刚度系数对模型颗粒流水平方向拉应力影响较大,增加轮胎与悬架阻尼系数对垂直方向颗粒流压应力与水平方向拉应力影响较小.In order to analyze the microscopic state mechanics response of asphalt pavement structure under vehicle load, the coupled discrete element model of a two-degree-of-freedom 1/4 vehicle model and a multi-layer subgrade-pavement was established. The results of the uniaxial compressive stress-strain test of each structural layer was compared with the experimental data under the same working conditions, and the microscopic parameters of each structural layer of the discrete element model was obtained through iterative operations. A multi-layer subgrade-pavement model was established by using the microscopic parameters of an asphalt pavement, and a certain degree of unevenness was set on the upper surface of the discrete element model. The 1/4 vehicle model was moved on the discrete element model of the pavement under a certain speed, and the response of various structures of the asphalt pavement (such as displacement and stress) were obtained under the dynamic load of the vehicle. Further, by varying the body suspension stiffness, body suspension damping coefficient, tire stiffness, and tire damping coefficient of the 1/4 vehicle model, the changes in internal stress of asphalt pavements under the influence of different vehicle parameters were obtained. The research results show that it can not only obtain the stress and deformation of each layer of asphalt pavement under the interaction of vehicle and road based on the discrete element theory, but also obtain the trend of particle flow in each structural layer of asphalt pavement, under the action of vehicle moving load. The dynamic displacement and stress response of the particle flow in each structural layer decrease with increase in the subgrade-pavement depth. The dynamic displacement of the upper base particle flow is less than 25% of the dynamic displacement of the upper layer particle flow, and the vertical stress of the particle flow in the lower layer is 50% of the vertical stress of the particle flow in the upper layer. The particle flow is subjected to bo

关 键 词：道路工程 车辆荷载 离散元模型 模型细观参数 车路相互作用 路面响应 

分 类 号：U414.1[交通运输工程—道路与铁道工程]