加筋砂土三轴试验细观参数对宏观特性影响分析  

Analysis of mesoscopic parameters of reinforced sand triaxial test influence on macroscopic characteristics

作　　者：王家全[1] 施春虎 王宇帆[1] 

机构地区：[1]广西科技大学土木建筑工程学院,广西柳州545006

出　　处：《广西科技大学学报》2014年第1期1-6,99,共6页Journal of Guangxi University of Science and Technology

基　　金：国家自然科学基金项目(51009030);广西自然科学基金项目(2011GXNSFB018003);广西防灾减灾与工程安全重点实验室开放课题(2012ZDK07);广西科技大学博士基金项目(院科博1011)资助

摘　　要：以室内加筋砂土三轴试验为基础,开发离散元PFC3D,建立加筋砂土三轴试验三维仿真模型,并与室内试验结果验证比较.在此基础上,进一步探讨摩擦系数、刚度比和孔隙率等细观参数变化对试样宏观力学特性影响的敏感程度.结果表明:增加摩擦系数、刚度比和减小孔隙率能明显提升应力-应变曲线的峰值强度,且高围压时效果更加明显;抗剪强度指标粘聚力和内摩擦角随细观参数变化影响的敏感程度由强到弱排序均为:孔隙率、刚度比、摩擦系数,内摩擦角与摩擦系数呈现正相关关系,而与孔隙率呈现负相关关系.The three-dimensional numerical models of reinforced sand triaxial tests are simulated based on the laboratory tests by PFC3D, which belong to the discrete element method. The simulation results are compared with the laboratory test results. Based on the results of lab triaxial tests, the influence of mesoscopic parameters changes on the macroproperties of sand sample are discussed. The mesoscopic parameters include friction factor, stiffness ratio of particle, etc. It is found that： Increasing friction factor, stiffness ratio and reducing porosity of particle can significantly improve the peak strength of stress-strain curves, and the effect is more obvious with high confining pressure. The influence of mesoscopic parameters changes on cohesive strength and internal frictional angle from strong to weak ordering are： porosity, stiffness ratio, friction factor. The internal friction angle showed positive correlation with friction factor, and negative correlation with porosity.

关 键 词：颗粒流 细观参数 三轴试验 

分 类 号：TU47[建筑科学—结构工程]