大断面软岩硐室开挖非线性力学特性数值模拟研究

运用三维有限差分数值计算软件 (FLAC3D) ,模拟分析了软岩大断面硐室围岩由于开挖方法、开挖顺序的不同而产生不同时效变形与应力状态的力学响应及变形特性。研究结果表明 ,软岩大断面硐室的开挖过程是和应力路径与应力历史密切相关的非线性不可逆过程 ,其开挖设计方案应采用软岩非线性大变形力学设计方法 ,即首先采用力学对策设计 ,然后进行过程优化设计 ,最后进行最优参数设计 ,才能保证硐室围岩在开挖过程中处于最佳稳定状态

Research on the non-linear mechanics characters of large section cavern excavating within soft rock by numerical simulation

In this paper, FLAC3D is adopted to simulate the mechanical behavior and deformation characteristics with different excavating method and excavating sequence of large section cavern within soft rock. The research results have showed that the excavating process is a non linear irreversible process tightly related with stress paths and stress history.The non linear mechanics design method, which include mechanics countermeasure design, process optimization design, optimized parameter design,should be adopted in excavation plan design of large section cavern within soft rock.So the surrounding rock of cavern should be in stable state.