%0 Journal Article
%T 道砟材料累积沉降量和形变模量的离散元分析<br>Discrete element analysis of settlement and deformation modulus of railway ballasts
%A 严颖
%A 赵金凤
%A 季顺迎&lt
%A br&gt
%A YAN Ying
%A ZHAO Jingfeng
%A JI Shunying
%J 铁道科学与工程学报
%D 2016
%X 针对铁路有砟道床中碎石材料在细观上的非规则形态,采用离散元模型构造道砟颗粒,并通过道砟箱试验数值分析道砟材料在往复荷载下的累积沉降量和形变模量。计算结果表明:在往复荷载作用下道砟材料的累积沉降量与加载次数呈指数关系,其形变模量随加载次数的增加不断增加并逐渐趋于稳定。在此基础上,对道砟摩擦因数和加载频率影响下的累积沉降量和形变模量进行离散元分析。随摩擦因数的增大,道砟颗粒间的咬合力不断增加,致使道砟材料的累积沉降量减小而有效刚度越大;随加载频率的增大,道砟材料更趋于密实排列,从而使其累积沉降量增大而形变模量降低。本文研究表明离散元模型在分析道砟材料力学特性方面具有较高的可行性,并有助于进一步揭示有砟铁路道床的累积变形规律。<br>This study investigates settlement and deformation modulus of railway ballasts under repeated loads through ballast box tests by using discrete element method and considering the irregular shapes of ballasts. Simulated results present an exponential relationship between settlement and loading cycles. Deformation modulus of ballasts increases with increasing loading cycles and tends to be constant. Based on the developed discrete element model, this study also explores the influential factors, such as friction coefficients of ballasts and loading frequency. The results show that settlement reduces and deformation modulus increases with increasing friction coefficients because of the increasing interlocking between particles. Settlement increases and deformation modulus reduces with increasing loading rates because of the corresponding compact packing. This study shows the feasibility and contribution of the discrete element method in the understanding of the mechanical characteristics of railway ballasts
%K 道砟材料
%K 离散元模型
%K 累积沉降量
%K 形变模量
%K 摩擦因数&lt
%K br&gt
%K ballasts
%K discrete element method
%K settlement
%K deformation modulus
%K friction coefficient
%U http://www.jrse.cn/paper/paperView.aspx?id=paper_311823