不良地质条件下排水隧洞开挖一次支护稳定分析

Stability Analysis on Primary Support in Excavation of Drainage Tunnel under Poor Geological Conditions

不良地质条件下排水隧洞开挖后的一次支护对于限制围岩变形、确保围岩稳定及隧洞结构安全具有重要作用。在考虑围岩初始地应力场的基础上,采用三维非线性有限元模型模拟了排水隧洞开挖及一次支护过程,分析了不良地质条件下(Ⅴ类围岩)的围岩应力及隧洞一次支护结构的稳定性,可为隧洞支护三维有限元结构设计优化和合理安排支护时机提供依据。

Primary support in excavation of drainage tunnel under poor geological conditions plays an important role in confining surrounding rock deformation,ensuring surrounding rock stability and tunnel structure safety.In this paper,based on initial in-situ stress field of surrounding rocks,discharge tunnel excavation and primary support are simulated by 3D nonlinear finite element model and element life and death method,surrounding rock stress and tunnel primary support structure stability under poor geological conditions(class V surrounding rocks) are analyzed so as to provide basis to tunnel support 3D finite element structure design optimization and proper support occasion.