三维锯齿型结构面直剪特性分析

Analysis of the Direct Shear Characteristics of the Structural Plane of Three Dimensional Indention Type

结构面特性对于岩体稳定性具有重要的影响,为了研究锯齿型结构面的强度和变形特征,利用数值计算软件建立了三维结构面岩体试样的计算模型,采用界面单元模拟结构面特性,得到结构面在正应力和剪应力作用下,结构面剪切强度与起伏角的关系、应力应变关系以及剪胀效应。结果表明,结构面起伏角对内摩擦角的影响程度大于对黏结力的影响程度;相对法向位移与相对切向位移关系曲线明显地随法向应力大小不同而呈现出不同的变化趋势;在不同的起伏角和正应力状态下,法向位移和剪切位移之间均符合线性关系。

The characteristics of the structural plane have a great influence on the stability of rock mass. In order to study the strength and deformation characteristics of indention structural plane, a numerical calculation software is used to build a three dimensional calculation model for the rock mass samples with structural planes. In the calculation model the interface element is used to model the structural plane, and the the characteristics of the structural plane under normal stress and shear stress are obtained, including the relationship between shear strength and roughness angle of the structural plane, the relationship between stress and strain, and the shear dilation effect. The results show that, （1） the effect of roughness angle of the structural plane on the internal friction angle is greater than that of cohesion; （2） the relationship between normal displacement and shear displacement sees a different trend for different normal stresses; while their relationship is linear.