【作者】 王文涛；

【导师】 朱维申；

【作者基本信息】 山东大学 ， 岩土工程， 2008， 硕士

【摘要】 裂隙岩体力学特性及其时效特征的研究一直为岩石力学与工程界所关注。本文综合应用岩石损伤力学、岩石流变力学、数值计算等理论方法,对裂隙岩体损伤流变耦合本构方程及工程应用做了一些初步的探讨。首先,针对裂隙岩体结构特征,从几何损伤的角度,引入了一个二阶张量来描述裂隙面对岩体的劣化效应。以裂隙面面积、裂隙面方向、裂隙面间距及密度作为损伤变量的主要影响因素,将多组裂隙面在各截面上的损伤贡献进行叠加来近似描述多组裂隙面的各向异性损伤。以西原模型作为描述岩体力学时效特性的基本模型,并通过对应原理将一维形式的西原模型流变本构方程转化为三维形式。最后根据等效应变假设,将二阶损伤张量引入流变本构方程,得到了基于西原模型的三维粘弹塑性损伤本构方程。在VC++6.0环境下,以FLAC3D Version 2.1数值计算通用软件为开发平台,编写了上述本构模型的程序块,实现了该软件本构模型的二次开发,并阐述了二次开发程序块的运行原理。最后,运用开发的本构模型,对双江口水电站地下洞室群开挖过程及围岩稳定性进行了粘弹塑性损伤分析,并与弹塑性计算进行了比较,从对比结果来看模型基本上是合理的。同时,根据计算结果,为地下洞室群的长期稳定性及安全性,提出了一些合理的建议。更多还原

【Abstract】 The study on the mechanics and time-dependent feature of fractured rock mass is always an important subject of rock mechanics and engineering. Based on the theoretical method of rock damage mechanics, rock rheological mechanics and numerical calculation, this paper makes a preliminary study on the damge and rheology coupled model of fractured rock mass and its engineering application.First, according to the structural characteristics of fractured rock mass and the geometric damage theory, we cite a second-order damage tensor to describe the deterioration of rock mass due to cracks. Taking the crack area, direction, space and density as the major influencing factors of the damage variable, we stack the damage contribution of groups of cracks on each section to describe the anisotropic damage approximatively. The Nishihara model is taken as the basic model to study the time-dependent characteristics of rock mass. And its one-dimensional constitutive equation is transformed into three-dimensional form. Eventually, by introducing the second-order damage tensor into the rheological constitutive equation on the basis of the equivalent strain hypothesis, the three-dimensional viscoelastic-plastic damage constitutive equation is deduced.Taking FLAC3D Version2.1 as the development platform, we compile the above constitutive model on the VC++6.0 environment, and realize the secondary development of FLAC3D. The operation principles of secondary development program is also described.In the end, the surrounding rock stability of the underground cavern group of Shuangjiangkou hydropower station is analysed by using the development program. And the results are compared with the ones obtained from the computation with elastic-plastic model. According to the comparative results, the model is basically reasonable. Meanwhile, some rational suggestions are put forward for the long-term stability and security of underground cavern group.更多还原