粗粒土与结构接触面的可逆性与不可逆性剪胀规律  

Reversible and irreversible dilatancy of soil-structure interface

作　　者：张嘎[1] 张建民[1] 

机构地区：[1]清华大学岩土工程研究所,北京100084

出　　处：《岩土力学》2005年第5期699-704,共6页Rock and Soil Mechanics

基　　金：国家自然科学基金资助项目(No.50279015);北京市自然科学基金重点资助项目(No.8011002)。

摘　　要：进行了粗粒土与结构接触面的单调和往返剪切试验,研究了接触面的剪胀特性。试验结果表明,接触面的剪胀体应变是由一个完全可逆性的体应变分量和一个不可逆性的体应变分量构成的。不可逆性剪胀体应变反映了接触面内的土颗粒破碎和剪切压密两种物态变化,其变化规律与接触面的应力相对位移关系的演化规律具有相似性,是接触面力学特性演化的一个重要量度。可逆性剪胀体应变存在相变点,并表现出明显的剪切异向性,该异向性的主要内因是由于剪切引起的结构面附近土的结构异向性。基于接触面受力变形机理分析,引入有效剪应变等概念,建立了剪胀方程。The volumetric strain due to dilatancy of soil-structure interface was studied based on test results. It is found to be composed of a reversible and an irreversible dilatancy component. The irreversible dilatancy component reflects the evolution of physical state including crushing and compression of the soil. And it exhibits similar change tendency to the evolution of stress-strain relationship response. Thus, the irreversible dilatancy component could be used to measure the evolution of the behavior of the interface. The reversible dilatancy component would dilate after the compression at first due to shear application. And it obviously exhibits aeolotropical behavior, which is induced by the structural aerotropy of soil near the structure due to shear application. The dilatancy equation was derived through introducing new concepts such as effective shear strain according to mechanism analysis.

关 键 词：接触面 可逆性剪胀 不可逆性剪胀 剪胀方程 

分 类 号：TU43[建筑科学—岩土工程]