离散元法分析集料接触特性对沥青混合料剪切疲劳寿命的影响  

Influence of aggregate contact characteristics on shear fatigue life of asphalt mixtures using discrete element method

作　　者：彭勇[1] 章秀芳 郭泽宇 陆学元 李彦伟[3,4] PENG Yong;ZHANG Xiu-fang;GUO Ze-yu;LU Xue-yuan;LI Yan-wei(Institute of Transportation Engineering,Zhejiang University,Hangzhou 310058,China;Anhui Transportation Holding Group Co.,Ltd.,Hefei 230088,China;Hebei Provincial Communications Planning and Design Institute,Shijiazhuang 050011,China;Research and Development Center of Transport Industry of Technologies,Materials and Equipments of Highway Construction and Maintenance,Shijiazhuang 050011,China)

机构地区：[1]浙江大学交通工程研究所,杭州310058 [2]安徽省交通控股集团有限公司,合肥230088 [3]河北省交通规划设计院,石家庄050011 [4]公路建设与养护技术、材料及装备交通运输行业研发中心,石家庄050011

出　　处：《吉林大学学报（工学版）》2023年第1期178-187,共10页Journal of Jilin University:Engineering and Technology Edition

基　　金：浙江省自然科学基金项目(LY15E080006).

摘　　要：基于CT断层扫描和图像处理采集到的沥青混合料内部结构信息,采用Matlab软件编写程序获取混合料内部集料接触特性,借助颗粒流软件PFC3D建立混合料剪切疲劳试验三维离散元模型,模拟考虑损伤的沥青混合料剪切疲劳寿命,研究集料接触特性对沥青混合料剪切疲劳寿命的影响,并对模拟结果加以试验验证。研究结果表明,考虑疲劳损伤的沥青混合料剪切疲劳三维离散元法可以较好地模拟沥青混合料剪切疲劳试验,得到的剪切疲劳寿命模拟值与试验值误差较小。集料接触点和总接触长度对沥青混合料剪切疲劳寿命影响显著,集料接触点数越多,总接触长度越大,混合料的剪切疲劳寿命越大;水平截面上集料接触方位角对沥青混合料剪切疲劳寿命影响较小,其两者间相关性不明显。此外,集料粒径和空隙率对沥青混合料中集料接触特性有较大的影响。相同的试验条件下,沥青混合料内部集料接触点数和总接触长度随集料粒径的增大而增加,随空隙率的增大而减少。The main purpose of this study is to investigate the influence of aggregate contact characteristics on shear fatigue life of asphalt mixtures using discrete element method(DEM). On the basis of the internal structure information of asphalt mixtures that was acquired by CT scanning and imaging technology,the aggregate contact characteristics were obtained using a program written in MATLAB. Three-dimensional(3D)discrete element models for the shear fatigue test of asphalt mixtures were established using a DEM code called Particle Flow Code in Three Dimensions(PFC3D)to simulate the shear fatigue life of asphalt mixtures considering fatigue damage. Simulation results were verified by performing laboratory shear fatigue tests. Research results show that the shear fatigue test of asphalt mixtures can be simulated by 3D DEM considering fatigue damage,and a comparison of simulation and laboratory results shows relatively good agreement. Aggregate contact point and contact length significantly influence the shear fatigue life of asphalt mixtures,and the shear fatigue life increases with the increase in aggregate contact point and contact length. The contact orientation of aggregates on the horizontal cross section marginally influences the shear fatigue life,and the correlation between them is not obvious. Furthermore,aggregate size and void content significantly influence the aggregate contact characteristics in asphalt mixtures. Under the same test conditions,the number of aggregate contact points and total aggregate contact length increase with the increase in aggregate size,while decrease with the increase in void content.

关 键 词：道路工程 沥青混合料 集料接触特性 剪切疲劳寿命 离散元法 

分 类 号：U414[交通运输工程—道路与铁道工程]