考虑围压效应的大理岩弹塑性耦合力学模型研究  

AN ELASTOPLASTIC COUPLING MECHANICAL MODEL FOR MARBLE CONSIDERING CONFINING PRESSURE EFFECT

作　　者：周辉[1] 杨凡杰[1] 张传庆[1] 徐荣超[1] 张凯[2] 

机构地区：[1]中国科学院武汉岩土力学研究所岩土力学与工程国家重点试验室,湖北武汉430071 [2]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221008

出　　处：《岩石力学与工程学报》2012年第12期2389-2399,共11页Chinese Journal of Rock Mechanics and Engineering

基　　金：中国科学院知识创新工程重要方向项目(KZCX2-EW-QN115);国家自然科学基金资助项目(50979104;41172288);国家自然科学基金资助项目(51079144);国家重点基础研究发展计划(973)项目(2010CB732006)对本文的资助

摘　　要：以锦屏T2b和T2 6y深埋大理岩循环加卸载试验结果为基础,进行如下研究:(1)分析不同围压下锦屏大理岩的弹性参数随内变量的演化规律,得到弹性模量与围压和内变量的定量关系;(2)基于Mohr-Coulomb屈服准则,得到其强度参数随内变量的演化规律;(3)考虑非关联流动法则,分析剪胀角随围压和内变量的演化规律,得到锦屏大理岩的剪胀角与围压和内变量的定量关系;(4)最终建立考虑围压效应的大理岩弹塑性耦合力学模型,并在有限差分软件FLAC3D中进行数值实现,用于模拟分析T2b大理岩的室内常规三轴压缩试验,结果表明,数值模拟与试验结果吻合很好,该模型可以很好地反映大理岩的主要力学特性。所提研究方法和研究结果对于提高深部工程围岩(特别是具有小变形破坏特性的硬脆性围岩)变形计算和稳定性分析的准确性具有重要的参考价值和借鉴意义。Based on the results of cyclic loading and unloading tests of two kinds of deep marbles 6 2y T and 2b T from Jinping II hydropower station,an elastoplastic coupling mechanical model considering confining pressure effect is proposed with taking the following aspects into consideration：（1） Evolution of elastic parameters of marbles with internal variable under different confining pressures is studied;and the quantitative relationships among elastic modulus,confining pressure and internal variable are proposed.（2） On the basis of Mohr-Coulomb yield criterion,the variation of strength parameter with internal variable is put forward.（3） Evolutions of dilatancy angle of Jinping marbles with internal variable and confining pressure are analyzed considering non-associated flow rule;and the quantitative relationships among dilatancy angle,confining pressure and internal variable are proposed.（4） Finally,the proposed mechanical model is embedded in FLAC3D using C＋＋ language,and used to simulate the conventional triaxial compression test results.It is shown that there is significantly better agreement between simulating results and test data,and the proposed mechanical model can reflect the main mechanical properties of marbles.Efforts of this paper can give an important reference for promoting numerical accuracy of deformation and stability for rockmass of deep engineering,especially for brittle rockmass with the characteristics of fracturing under small deformation.

关 键 词：岩石力学 深埋大理岩 围压效应 弹塑性耦合 力学模型 数值模拟 

分 类 号：TU45[建筑科学—岩土工程]