某引水隧洞深埋软岩洞段围岩变形量敏感性分析

Sensitive analysis of rock mass deformation in a deep-buried soft rock section of a water diversion tunnel

通过深入分析西南某深埋长引水隧洞软岩洞段地应力钻孔实测资料,得到了水平构造应力侧压系数随隧洞埋深的变化规律。在此基础上,采用快速应力边界法开展数值计算,探讨洞型、围岩类别、埋深等因素对该段围岩变形量的影响及其变化规律,开展了围岩变形量敏感性分析。结果表明,该洞段围岩变形量随围岩类别降低而增大,随埋深增加而增大。研究成果可为该类隧洞深埋软岩洞段开挖支护设计提供借鉴。

Through deeply analyzing the ground stress data in bore holes of a deep - buried tunnel in Southwest China, we ob- tain the relationship between lateral pressure coefficient of horizontal tectonic stress and the buried depth of the tunnel. Based on numerical simulation of quick stress boundary method, the influence of the tunnel shape, rock classification, buried depth etc. on tunnel rock mass deformation is analyzed and a sensitive analysis is carried out. The results show that the deformation of rock mass in the presented section increases with decline of rock mass classification and with the increase of the buried depth of the tunnel. The results could provide valuable reference for support design of similar deep - buried and soft rock tunnel.