低地应力区地下洞室开挖后围岩位移二维离散元数值模拟

2D Discrete Element Method simulating displacement characteristics of surrounding rockmass of underground excavation in the low ground stress region

以西北某水利工程地下洞室为例,对低地应力状态下洞室开挖后围岩位移变化及其相应特征,采用了二维离散元法进行数值模拟研究,结果表明:低地应力区地下洞室开挖后围岩位移主要发生在拱顶位置,而发生在侧壁水平位置上的围岩位移量则明显不及前者,这说明低地应力区地下洞室开挖后围岩变形破坏主要发生在洞顶垂直方向,侧壁水平方向围岩变形破坏规模和强度均不及前者.

2D Discrete Element Method(DEM) is used to simulate the displacement characteristics of surrounding rockmass in the low ground stress region,and one water conservancy underground excavation engineering project in Northwest China is taken as an example. The simulated results show that displacement amount would be formed at the roof and both sides,but displacement amount at the roof of underground excavation is bigger than those at the both sides. It also means that the deformation and failure would be formed at the roof and both sides of underground excavation,but the deformation and failure of rockmass at the roof of underground excavation are especially more serious than those at both sides.