基于PFC^(2D)的路基填料细观参数影响研究  

Study on the Influence of Mesoscopic Parameters of Subgrade Filler Based on PFC^(2D)

作　　者：许腾 李炜 曹俊仁 XU Teng;LI Wei;CAO Junren(Huzhou Traffic&Plan Design Institute,Huzhou 313000,China)

机构地区：[1]湖州交通规划设计院,浙江湖州313000

出　　处：《天津建设科技》2025年第1期30-32,80,共4页Tianjin Construction Science and Technology

摘　　要：为了快速、准确地确定离散单元法PFC数值模拟路基填料样的细观参数,基于PFC^(2D)离散元软件,研究直剪试验时不同细观参数(包括模量、刚度比、摩擦系数、竖向应力等)对剪切位移-剪切应力曲线及抗剪强度的影响。结果表明:模量和刚度比对剪切位移-剪切应力曲线的初始斜率和峰值大小(剪切强度)有影响,随着模量和刚度比的增加,初始斜率和峰值大小会不同程度增加;而摩擦系数对初始斜率和峰值强度等均有影响,竖向应力增大会使抗剪强度增加,可以通过抗剪强度和竖向应力的关系曲线标定内摩擦角和黏聚力。同时还对线性本构模型和平行黏结模型的使用情况进行了分析,线性本构模型更适合模拟无黏结类粒料填料,平行黏结模型则更适合模拟路基土填料。In order to determine the mesoscopic parameters of simulated Subgrade Filler soil samples parameters quickly and accurately.In this paper,based on PFC^(2D)discrete element software,the effects of different microscopic parameters(including modulus,stiffness ratio,friction coefficient,vertical stress,etc.)on shear displacement-shear stress curve and shear strength during direct shear test are studied.The results show that the modulus and stiffness ratio have influence on the initial slope and peak value(shear strength)of the shear displacement-shear stress curve.With the increase of the modulus and stiffness ratio,the initial slope and peak value will increase to different degrees.The friction coefficient has an effect on the initial slope and peak strength,and the increase of vertical stress will lead to the increase of shear strength.The internal friction Angle and cohesion can be determined by the relationship curve between shear strength and vertical stress.At the same time,the application of linear constitutive model and parallel bond model is also analyzed.Linear constitutive model is more suitable for simulating unbonded granular filler,while parallel bond model is more suitable for simulating subgrade soil filler.

关 键 词：直剪试验 颗粒流 细观参数 路基 填料 

分 类 号：U416.1[交通运输工程—道路与铁道工程]