裂隙岩体的弹塑性本构模型及有限元分析

A Constitutive Model of Jointed Rock Masses and Its Finite Element Analysis

首先用弹塑性理论建立起裂隙的非线性应力应变关系，然后引入表征单元体的概念，定义了平均应力及平均应变．在此基础上建立了裂隙岩体的本构模型．该模型克服了应变叠加原理的不足，同时有效地模拟了裂隙的强烈非线性变形及剪胀等特性．编制了相应的三维有限元分析程序，并给出了算例分析．计算表明，裂隙的存在对整个岩体的变形及稳定性起控制作用，模型可直接应用于裂隙岩体的渗流应力耦合分析研究．

The mechanical behavior of joints is represented by the classical theory of elasto plasticity.Based on this,the stress strain relations of the jointed rock masses are formulated by taking the volume average of the stress and strain inside a representative volume element where the evaluation of the relative displacement across the joints is required.The model overcomes shortcomings of the strain superposition principle,and predicts joint responses,such as non linearity and dilatancy.The finite element code based on the model is established and applied to engineering problems.The model can be directly applied to the coupled stress and fluid flow analysis for jointed rock masses.