穿越断层破碎带深埋隧道围岩失稳的突变理论分析

The cusp catastrophe theory analysis for instability of deep-buried tunnels surrounding rock through fault fracture zone

在分析隧道开挖引起断层破碎带围岩失稳的基础上,认为深埋隧道断层破碎带围岩的失稳是一种突发破坏现象。根据总势能原理,建立了穿越断层破碎带深埋隧道围岩失稳尖点突变模型,推导出失稳的力学判据条件。分析结果表明,断层破碎带围岩的突发失稳与几何-力学参数ζ和综合刚度比k相关。最后以建中隧道修建过程中的三处典型断层破碎带为例,运用建立的尖点突变模型进行分析。分析结果与实际施工围岩情况一致。研究成果可为预防深埋隧道围岩失稳、采取合理的施工工艺和支护措施提供参考依据。

By analyzing surrounding rock with fault fracture zone instability caused by tunnel excavation, surrounding rock with fault fracture zone instability of deep-buried tunnels is considered as a sudden failure phenomenon. Based on the total potential energy principle, the cusp catastrophic model for instability and failure of deep-buried tunnel surrounding rock through fault fracture zone is established, and the mechanical judge condition of instability is derived. The analysis results showed that sudden instability of fault fracture zone surrounding rock is related by rock geometry-mechanic parameter ζ and comprehensive stiffness ratio k.Finally, three typical fault fracture zones of Jian Zhong Tunnel were analyzed with the cusp catastrophic model. The analysis result accords with the reflection of surrounding rock in practical construction. The research achievement in this article not only offers references for preventing instability and failure of deep-buried tunnels, but also gives an important guidance for reasonable construction technique of supporting measures.