结构性土的微观破损机理研究  

Study on mechanism of micro-failure of structured soils

作　　者：李建红[1] 沈珠江[1] 

机构地区：[1]清华大学水利水电工程系/水沙科学与水利水电工程国家重点实验室,北京100084

出　　处：《岩土力学》2007年第8期1525-1532,1550,共9页Rock and Soil Mechanics

基　　金：国家自然科学基金项目(No.10272062;No.50479007)

摘　　要：在前人研究的基础上,针对凸多面体相互接触的性质,推导了三维状态下的微观接触力和宏观应力的关系,并应用于结构性土的研究中。对结构性土,采用以土颗粒之间的胶结和组构为基本研究对象的研究方法,在二元介质理论框架内推导出结构性土破损规律及迭代公式,提出3种破损方式(剪碎、压碎、混合型),同时推导了宏观的柔度张量;对各向同性的结构性土,在球应力加载条件下的破损规律以及变形规律进行了研究,得到了解析解,简单分析的结果与实际相符。Based on previous study, the authors deduced the three-dimensional relationship between micro-contact force and the macro-stress on convex polyhedron. Meanwhile the authors proposed the way dealt with the structured soils through investigating the properties of soil fabric and bonding between soil granulae. Following the conception of binary medium of structured soils presented by SHEN Zhu-jiang, this paper presents three models of failure of bonding under macro-stress and provides the equation for iterative calculation to derive the macro-compliance tensor. As an example, the structured soil behavior with the isotropic bonding and isotropic fabric under the isotropic loading has been studied and the closed-form solution of the failure development and the stress relationship has been derived. The investigations show that the failure of structured soils is caused by both of micro-sheafing and micro-tension, which is corresponding with the real experimental study.

关 键 词：结构性土 微观接触力 组构 破损规律 

分 类 号：TU411.92[建筑科学—岩土工程]