基于能量耗散的脆性岩体张开位移数值模拟

Simulation of opening displacement of brittle rockmass at point of energy dissipation

高地应力大型地下洞室群的稳定性问题一直是众多岩石力学工作者的关注热点。从张开位移的产生机制出发,结合能量耗散原理,对高地应力脆性岩体能量耗散本构方程及其工程应用做了初步的探讨。从能量耗散的角度出发,引出了加、卸荷作用时的变弹模模型,并将该理论应用到弹脆性本构方程中;利用FLAC3D软件的二次开发功能,在C++的环境下进行上述模型程序模块的编写工作,实现模型的二次开发;以锦屏一级大型地下洞室群为工程背景,进行实际工程的开挖模拟计算。模拟结果表明,考虑能量耗散的弹脆性模型能更真实地反映实际开挖情况,其结果对类似工程具有一定的指导意义。

The stability of large underground caverns in high geostress area has always been the hot topics of many rock mechanics professors＇ attention.Based on the happening mechanism of opening displacements and considering the theory of energy dissipation,this paper makes a preliminary study of the constitutive equation of brittle rockmass in high geostress zone and their engineering application.First,a variational-modulus model has been received during the unloading course from the point of energy dissipation and this aspect is considered in the constitutive equation.Dissipation of energy can be gained from the theory of crack growth.Second,taking advantage of FLAC3D,we compile the above constitutive equation model on the Microsoft Visual C＋＋ environment,and realize the secondary further development of FLAC3D.Third,the stability of surrounding rock and the excavation step in the large underground caverns of Jinping hydropower station are simulated by the developed program.The results indicate that this variational-modulus model is closer to real excavation.It offers some instructions to similar projects.