结构面剪切特性的试验与数值模拟分析  

Test for Shear Characteristics of Structural Plane and Its Numerical Simulation Analysis

作　　者：周莲君[1,2] 彭振斌[1] 何忠明[3] 彭文祥[1] 

机构地区：[1]中南大学地学与环境工程学院,长沙410083 [2]中南大学湖南中大设计院有限公司,长沙410075 [3]中南大学资源与安全工程学院,长沙410083

出　　处：《科技导报》2009年第4期31-35,共5页Science & Technology Review

基　　金：中南大学博士后基金项目(200717);湖南省交通厅科研基金项目(200020)

摘　　要：结构面的性质对岩体工程稳定性具有重要意义，通过室内试验和数值模拟，分析了结构面在直剪条件下的应力和变形特征，得到：（1）直剪试验过程中，剪力-剪切位移之间的关系逐渐从线性关系转化为非线性关系；当剪应力将要达到峰值剪切强度时，切向位移突然增大。岩体已开始沿结构面剪坏；（2）试样剪切强度与正应力之间符合Mohr—Coulomb线性关系；数值计算得到的应力应变关系与室内试验得到的结果相同，说明了数值试验的可靠性；（3）结构面剪应力的分布从结构面施加切向位移速率的一端向另一端逐渐增大；（少随着法向应力的增大，最大剪应力分布区域基本上没有变化，说明法向力的大小对结构面剪应力的分布影响较小；并且根据Mohr-Coulomb理论。正应力在结构面上的分布情况类似于剪切力的分布情况。The characteristics of structural plane are very important to the stability of rock mass. In this paper, the stress and deformation characteristics of structural plane under direct shear conditions are analyzed based on laboratory tests and numerical simulations. It is shown that, （1） during the process of direct shearing, the relationship between shear stress and shear displacement changes from the linear form to a nonlinear form; after the shear stress of structure plane reaches the peak magnitude of shear strength, the shear displacement increases abruptly, and rock mass fails by slipping under shear stress; （2） relationship between shear strength and normal stress can be well described by the linear form of the Mohr-Coulomb criterion; the relationships between stress and strain characteristics obtained from the numerical calculation are the same as obtained from the laboratory tests, which has validated the numerical modeling; （3） the stress on the structural plane increases from the side of loading to the other side; （4） with the increase of normal stress, the distribution area of maximum shear stress does not vary much, which indicates relative small effect of normal stress on the shear stress distribution of structure plane; while according to the theory of Mohr-Coulomb criterion, the distribution of normal stress is similar to the distribution of shear stress.

关 键 词：结构面 剪切特性 数值分析 

分 类 号：TU458[建筑科学—岩土工程]