基于双折减系数法的隧道掌子面稳定性分析

在隧道施工过程中，掌子面发生坍塌的事故屡见不鲜，特别是在破碎岩体隧道开挖后，围岩自稳能力差，易出现坍塌破坏。通过研究掌子面破坏时楔形滑动体力与力矩的静力平衡，采用双折减系数法分析跨断层处破碎带对隧道施工过程中掌子面稳定性的影响。结果表明:断层倾角逐步减小时，断层泥体积增大；由于断层泥强度较小，掌子面不稳定，须采取加固措施。

Analysis on Stability of Tunnel Face Based on Double Reduction Coefficient Method

During the construction of tunnels, the collapse of the tunnel face is not uncommon. Especially in the broken rock, the self-stabilization of the surrounding rock is poor.or even no self-stabilization time, the construction is prone to collapse damage. In this paper, by analyzing the static balance of wedge-shaped sliding force and moment when the face is broken, the influence of the inclination angle of the cross-fault fracture zone on the stability of the face during the tunnel construction is analyzed with double reduction coefficient method. The results show that when the fault inclination angle is reduced, the fault gouge volume is increased. The reinforcement measures must be adopted due to weak strength of fault gouge and unstable face