杨房沟水电站地下厂房围岩稳定分析

杨房沟水电站地下厂房具有“跨度大、边墙高、规模大”的特点,开挖过程中出现不同的围岩变形破坏问题。笔者通过现场调查分析,总结了地下厂房下游边墙的三类边坡破坏模式:应力型破坏、结构面型破坏、结构面~应力组合型破坏,其中,结构面控制型为主要变形破坏模式。依据不同变形破坏模式,在系统支护的基础上,采取相应的加强支护措施,经支护后,监测数据表明围岩稳定。其研究成果对以后大型地下洞室的围岩稳定分析及设计施工具有借鉴意义。

Analysis on Stability of Surrounding Rock in Underground Powerhouse of Yangfanggou Hydropower Station

The underground powerhouse of Yangfanggou Hydropower Station features large span,high sidewall and large scale.Deformation failure of different surrounding rocks occurred during excavation.Through field investigation and analysis,three types of slope failure of the downstream sidewall in the underground powerhouse are summarized in this paper:stress failure,structural plane failure,and combined structural plane and stress failure.Among them,the structural-plane controlling failure is the main type.According to different deformation failure types,based on the system support,the corresponding reinforcement and support measures are taken as per different failure types.After the support,the monitoring data shows that the surrounding rock is stable.The research results provide reference for the stability analysis,design and construction of large underground caverns.