基于Cosserat连续体的颗粒破碎影响研究  

Study of effect of particle breakage based on Cosserat continuum

作　　者：余村[1] 楚锡华[1] 唐洪祥[2] 徐远杰[1] 

机构地区：[1]武汉大学工程建筑工程学院,武汉430072 [2]大连理工大学土木建筑工程学院,辽宁大连116024

出　　处：《岩土力学》2013年第S1期67-72,79,共7页Rock and Soil Mechanics

基　　金：国家自然科学基金资助(No.10802060;No.11172216);国家重点基础研究发展计划项目资助(No.2010CB732005;No.2010CB731502)

摘　　要：颗粒破碎对颗粒材料宏观力学行为有重要影响。结合Hardin的破碎经验公式,将表征破碎程度的破碎参量与Cosserat连续体的内部长度参数相关联,形成一个基于Cosserat连续体且能考虑颗粒破碎的弹塑性模型。数值算例主要考察了颗粒破碎对颗粒材料承载能力、塑性应变及局部化行为的影响,数值结果表明,颗粒破碎主要发生在剪切带内,颗粒破碎使得剪切带明显变窄且剪切带内外等效塑性应变梯度明显增大。Particles' breakage has an important effect on the macromechanical behavior of granular materials.An elastoplastic model combined with an experiential crushing equation is suggested for crushable granular materials based on Cosserat continuum,Hardin's definition of relative breakage r B,which is used to quantify the extent of crushing,can be obtained from the crushing equation according to normal crushing stress.The internal length scale of Cosserat continuum theory is related to the average particle size of granular materials;and the evolution of which is computed by the relative breakage r B.Numerical examples focus mainly on the effect of particle crushing on the bearing capacity and localization of plastic strain.Numerical results illustrate that particles crush mainly in shear band,and shear band obviously becomes narrow and the equivalent plastic strain gradient increases when considering crushing.

关 键 词：颗粒材料 Cosserat连续体 颗粒破碎 应变局部化 

分 类 号：TV41[水利工程—水工结构工程]