摘要
猴子岩地下厂房区域地质构造复杂,洞室群埋深大,位于以水平构造应力为主的高—极高地应力区。与一般高地应力情况不同的是,猴子岩厂区第一、第二主应力均较高,分别达到36.43 MPa和29.82 MPa,使得高地应力对洞室高边墙的不利影响不能通过调整厂房轴线来规避,这为洞室施工和支护设计带来较大挑战。从工程施工过程中出现的变形破坏现象以及位移、支护应力监测资料、声波检测资料入手,归纳高第二主应力下大跨度地下洞室群的变形破坏特征为:1岩爆现象普遍;2围岩变形量及破坏深度大;3锚固支护结构负荷水平高。对围岩变形破坏机理作初步探讨,并根据支护效果总结了高第二主应力下支护设计和支护措施的经验,可为高第二主应力条件下大跨度洞室围岩的稳定分析提供参考。
The underground powerhouse of Houziyan hydropower station is located in high situ stress （mainly horizontal tectonic stress） region with complex geological conditions and big buried depth.Its first principal stress and intermediate principle stress reaches 36.43 MPa and 29.82 MPa respectively.The adverse impact couldn＇t be avoided by adjusting the powerhouse axis,hence posing great challenge to the construction and support design.With this project as an example,we summarize the deformation features of large-span underground caverns with high intermediate stress,and discuss the deformation mechanism of surrounding rock mass according to the deformation data,support monitoring data and acoustic detection data during construction.It was found that 1） rockburst is common ;2） the deformation and failure depth are large ; 3） the anchor support structure has big load level.The results of fast feedback analysis during construction period,the situ monitoring data and the acoustic detection data are used to verify the effectiveness of the support measures.We also summarized some experiences and lessons in this regard.
出处
《长江科学院院报》
CSCD
北大核心
2014年第11期108-113,119,共7页
Journal of Changjiang River Scientific Research Institute
关键词
高第二主应力
脆性岩体
地下洞室群
围岩变形破坏
支护措施
high intermediate principle stress
brittle rock mass
underground caverns
deformation and damage of surrounding rock
support measures
