浅埋隧洞围岩稳定性的数值模拟

Numerical Simulation of Surrounding Rock Stability of Shallow Buried Tunnel

为解决浅埋隧洞开挖过程遇到的岩体稳定性问题,利用数值模拟软件3DEC模拟济源市某隧洞的开挖过程,计算围岩块体的位移、应力和塑性区,分析围岩节理强度对围岩稳定性的影响,最后提供支护方案。模拟结果表明,开挖过程中,左侧墙和拱顶的块体均会产生失稳,从而引发围岩坍塌;增大块体节理强度,围岩的稳定性会显著提高;增加支护措施后,拱顶和左侧墙最大位移均在8mm左右,与现场监测结果接近。

In order to solve the problem of rock mass stability encountered in the excavation process of a shallow tunnel,the numerical simulation software 3DEC was used to simulate the excavation process of a tunnel in Jiyuan City,calculate the displacement,stress and plastic zone of the surrounding rock block,analyze the influence of the joint strength of the surrounding rock on the stability of the surrounding rock,and finally provide a support scheme.The simulation results show that both the left wall and the arch block will be unstable during excavation,which will lead to the collapse of surrounding rock.The stability of surrounding rock will be improved significantly with the increase of block joint strength.After the addition of supporting measures,the maximum displacement of the vault and the left wall is about 8 mm,which is close to the field monitoring result.