层间错动带影响下巨型地下洞室围岩变形及支护措施研究  

Study on Stability and Support Measures of Giant Underground Cavern under Influences of Interlayer Shear Belt

作　　者：苏锋 SU Feng(PowerChina Northwest Engineering Corporation Limited, Xi'an 710065,China)

机构地区：[1]中国电建集团西北勘测设计研究院有限公司,西安710065

出　　处：《西北水电》2020年第4期37-42,共6页Northwest Hydropower

摘　　要：白鹤滩水电站地下洞室群规模宏大且围岩地质条件复杂,软弱层间错动带影响下的地下洞室群开挖围岩稳定性及支护设计难度成为白鹤滩水电工程建设当中的关键技术问题。以右岸7号尾调室受层间错动带斜切影响为例,采用3DEC数值分析软件对其在不同支护方案下围岩和层间错动带变形的控制效果进行分析,探讨层间错动带分布位置对系统支护方案和局部加强支护方案的影响。研究表明:7号尾调室开挖围岩整体稳定性良好,系统支护方案满足维持整体稳定要求,但在层间错动带C4、C5局部影响范围内,需进一步采取针对性的加强支护措施,从而加强局部围岩的安全储备。研究工作的成果可为类似深埋地下工程施工及支护方案的确定提供参考。Baihetan hydropower station is characterized by the large scale underground caverns and complicated geological conditions.The stability of the surrounding rock excavation and the difficulty of support design of the underground cavern group under the influence of the weak interlayer dislocation zone have become the difficulty in the construction of the Baihetan Hydropower Project.Taking the No.7 tailrace surge chamber on the right bank affected by the oblique cutting of the interlayer dislocation as an example,the 3DEC numerical analysis software is used to analyze the control effect of the surrounding rock and the interlayer dislocation zone deformation under different supporting schemes and to discuss the influence of the position of the dislocation zone on the system support and the local reinforced support scheme.The study shows that the overall stability of the surrounding rock excavation of No.7 tailrace surge chamber is good,and the system support scheme meets the requirements for maintaining overall stability.However,it is necessary to further adopt reinforcement support measures in the local influence range of the interlayer shear belt C4 and C5.The study result can provide a reference for similar underground engineering construction and support schemes.

关 键 词：地下洞室 层间错动带 断层 系统支护 数值模拟 

分 类 号：U453.2[建筑科学—桥梁与隧道工程] TU457[交通运输工程—道路与铁道工程]