代冲溪水库重力坝坝基宽大断层带处理措施研究  

Study on Sensitivity of Geological Parameters of Soft Rock Dam Foundation in Wide Fault Zone

作　　者：肖鸿 刘羿 荣冠[2] XIAO Hong;LIU Yi;RONG Guan(Power China Guiyang Engineering Corporation Limited,Guiyang 550000,China;The State Key Laboratory of Water Resources Engineering and Management,Wuhan University,Wuhan 430072,China)

机构地区：[1]中国电建集团贵阳勘测设计研究院有限公司,贵州贵阳550000 [2]武汉大学水资源工程与调度全国重点实验室,湖北武汉430072

出　　处：《中国农村水利水电》2025年第1期175-181,共7页China Rural Water and Hydropower

摘　　要：代冲溪水库重力坝坝基发育23 m宽的断层破碎带,破碎带岩体力学特性较弱,在大坝的施工、蓄水和运行过程中会对坝基的稳定性产生重要影响。基于工程地质条件和岩体力学参数提出了坝基处理的微拱形混凝土塞置换基础方案,并开展了三维有限差分数值模拟计算和坝基F1断层岩石力学参数的敏感性分析。研究得出,在宽大断裂带软基岩体情况下,变形模量差异和断层带的弱承载力导致坝基的不均匀变形现象明显。通过微拱混凝土塞置换之后,蓄水过程坝基承载力及重力坝应力变形均满足要求。由于混凝土塞能够较好的发挥作用,断层破碎带参数的变化对大坝和坝基应力变形影响被削弱。相关研究为跨越宽大断层重力坝的基础处理提供了重要的参考价值。A 23 m wide fault fragmentation zone is developed at the foundation of a medium-sized reservoir gravity dam in Southwest China,and the mechanical properties of the rock body in the fragmentation zone are weak,which will have an important impact on the stability of the dam foundation during the construction,impoundment and operation of the dam.Based on the engineering geological conditions and rock mechanical parameters,a micro-arch concrete plug replacement foundation scheme for dam foundation treatment is proposed,and three-dimensional finite element calculations and sensitivity analyses of rock mechanical parameters of the F1 fault at the dam foundation are carried out.It is concluded that in the case of soft bedrock body with wide fracture zone,the difference of deformation modulus and the weak bearing capacity of the fault zone lead to the uneven deformation phenomenon of the dam foundation.After the replacement of the concrete plugs by micro-arch,the load carrying capacity of the dam foundation and the stress deformation of the gravity dam during the impoundment process meet the requirements.As the concrete plugs can work well,the influence of the variation of fault fracture zone parameters on the stress and deformation of the dam and dam foundation is weakened.The study provides an important reference value for the foundation treatment of gravity dams across wide faults.

关 键 词：重力坝 断层带 坝基处理 变形稳定 敏感性分析 

分 类 号：TV743[水利工程—水利水电工程]