考虑岩体各向异性强度的隧洞围岩稳定性分析

岩体中普遍存在着大量的节理裂隙等不连续面,这些不连续面对岩体的强度有着重要的影响。以具有较密集成组节理的岩体为研究对象,以Drucker-Prager准则和裂隙应力张开准则为基础,分别考虑岩块和节理面各自的物理力学性质,研究岩体在各向异性强度准则下的理论方法,并建立了岩体各向异性本构模型,用以描述节理岩体在强度方面的各向异性及其破坏特征。将该模型用于隧洞围岩稳定性分析工程中,研究表明,该模型可以较好地解释节理岩体围岩的破坏特征,与工程实践相符。研究成果对我国地下石油、核废料储存以及深埋地下工程的设计与施工具有重要的指导意义。

Stability Analysis of Surrounding Rock of Tunnel in Consideration of Anisotropic Strength of Rock Mass

Surface of discontinuities as joint and fissure are ubiquitous in rock masses.The surface of discontinuities significantly affect the strength of the rock masses.According to the physical and mechanical characteristics of joint and rock matrix,the theory and method were studied for anisotropic strength criteria of rock mass.Based on the Drucker-Prager criterion and stress-based joint opening criterion,a composite constitutive model of rock mass with densely distributed joint was proposed and it can depict the anisotropic characteristics of rock strength and progressive failure characteristics.The proposed model was used to simulate the construction of tunnel.Results show that the model can be used to explain deformation and failure phenomenon of the surrounding rock fairly,which are in accordance with engineering practice.The study give a reference to exploitation of underground oil,preservation of nuclear waste and design and construction of underground engineering in China.