基于颗粒破碎的粗粒土剪切强度的模拟分析  

PFC^(2D) SIMULATION OF ROCKFILL SHEAR STRENGTH BASED ON PARTICLE FRAGMENTATION

作　　者：徐永福[1,2] XU Yongfu(Department of Civil Engineering,Shanghai Jiao Tong University,Shanghai 200240;Wentian College of Hohai University,Maanshan 243000)

机构地区：[1]上海交通大学土木工程系,上海200240 [2]河海大学文天学院,马鞍山243000

出　　处：《工程地质学报》2018年第6期1409-1414,共6页Journal of Engineering Geology

基　　金：国家自然科学基金面上项目(41472251);国家自然科学基金重点项目(41630633)资助

摘　　要：颗粒破碎在岩土工程领域是很常见的现象,土工试验中无法显示颗粒破碎过程及其影响,本文采用离散单元软件PFC2D模拟了考虑颗粒破碎影响的粗粒土的直剪试验,给出了考虑颗粒破碎的粗粒土直剪试验的模拟方法,分析粗粒土的剪应力-剪切位移关系、剪胀和剪切强度等宏观力学行为,探讨基本颗粒间黏聚力、单颗粒孔隙率和粗粒土试样的孔隙率对剪切强度的影响。结果表明:颗粒破碎对剪切强度的破碎准则有影响,颗粒不破碎试样的剪切强度符合Mohr-Coulomb准则;颗粒破碎试样的强度包络线是幂函数关系。PFC^2D code is used to simulate the direct shear tests of rockfills,taking into consideration of the particle crushing. The methods to establish the model of the rockfill sample and conduct the tests are given. The results obtained from the numerical simulation are analyzed from several aspects,such as the characteristics of stress-strain relationship,volume strain and shear strength. The effect of the contact-bond strength between basic particles,the porosity of the single rock particle and the porosity of the rockfill material on the shear strength of the rockfills are also discussed.

关 键 词：粗粒土 直剪试验 剪切强度 颗粒破碎 分形 PFC^2D数值模拟 

分 类 号：P624.3[天文地球—地质矿产勘探]