新型节理岩体损伤流变模型数值模拟研究

Numerical simulation of a new damage rheology model for jointed rock mass

越来越多的地下大型水电站洞室群处在大埋深、高地应力、高孔压的地质环境中,流变现象较为明显。同时,由于岩体中节理裂隙的存在,对围岩产生弱化效应,使得洞室的稳定性分析更为复杂。针对这些特点,综合考虑损伤和流变的影响,推导出基于西原体模型的黏弹塑性损伤本构模型。此外,利用三维快速拉格朗日FLAC3D软件的二次开发功能,以VC++作为开发平台,将包含差分形式的本构方程程序化,生成动态链接库文件(DLL文件),通过FLAC3D主程序进行调用。从而,开发出了新型节理岩体的FLAC3D损伤流变本构模型。将此模型应用于双江口洞室群工程实例,完成了洞室稳定性分析计算和指导施工设计。结果表明:将该损伤流变模型用于模拟大型地下洞室群的开挖、分析其稳定性,具有较强的可行性,可用于指导实际的工程施工。

More and more large underground power houses are under the geological environment of large buried depth,high ground stress and high pore water pressure.At the same time,it is complicated to analyze the stability of underground houses because of the existence of joints in the rock mass.The joints make intension of the rock mass decrease.According to these characteristics,a new visco-elastoplastic mechanical model is deduced.The model has a comprehensive consideration of damage and rheology.Besides,regarding VC＋＋ as the plat form,the secondary development function of FLAC3D is employed to make a program of this constitutive equation.It is a dynamic link library（DLL） and can be used by the main program of FLAC3D.A new damage rheology FLAC3D rock mass is developed.In the project of Shuangjiangkou large underground power houses,the program model for joins is used to analyze the ability of houses and to guide the design of engineering.The results show that it is quite strong feasible to use this new damage rheology FLAC3d model to simulate the excavation of large underground power houses and analyze the stability.The analytic results can be used to guide the construction of engineering.