白鹤滩水电站蓄水过程对左岸地下厂房围岩稳定性影响评价  

Evaluation of the Impact of Reservoir Impoundment on the Stability of Surrounding Rock in the Left Bank Underground Powerhouse at Baihetan Hydropower Station

作　　者：童政 俞钟杰 邱钦焱 张胡琦 谭尧升 荣冠[1,2] TONG Zheng;YU Zhong-jie;QIU Qin-yan;ZHANG Hu-qi;TAN Yao-sheng;RONG Guan(State Key Laboratory of Water Resources Engineering and Management,Wuhan University,Wuhan 430072,Hubei Province,China;Key Laboratory of Rock Mechanics in Hydraulic Structural Engineering,Ministry of Education,Wuhan University,Wuhan,430072,Hubei Province,China;China Three Gorges Construction Engineering Corporation,Chengdu 6100411,Sichuan Province,China)

机构地区：[1]武汉大学水资源工程与调度全国重点实验室,湖北武汉430072 [2]武汉大学水工岩石力学教育部重点实验室,湖北武汉430072 [3]中国三峡建工(集团)有限公司,四川成都610041

出　　处：《中国农村水利水电》2025年第4期210-218,共9页China Rural Water and Hydropower

基　　金：中国长江三峡集团有限公司科研项目(BHT/0811)。

摘　　要：白鹤滩水电站是我国第二大水电站,左岸地质条件复杂,地下洞室规模巨大,蓄水后厂房区域存在渗水现象,渗流作用对围岩变形和稳定性具有一定影响。为研究左岸地下洞室在蓄水过程的围岩稳定性问题,采用现场监测数据和数值模拟相结合的方法,分析库水位抬升影响厂区围岩变形的作用机制。利用监测数据分析厂区地下水自由面、渗压、渗漏量等渗流场特征,揭示厂房围岩变形规律和应力变化趋势;基于稳定渗流理论,采用有限单元法模拟上库蓄水至640、775和816m水位时的左岸渗流场;通过有限差分数值仿真软件FLAC3D,研究地下水渗流对围岩变形的影响。数值模拟与监测结果对比反映两者变形规律基本一致,研究结果表明:蓄水过程中,白鹤滩水电站左岸地厂围岩变形与上库水位呈正相关,岩体变形量随库水位上升而逐渐增大,上游岩台最大位移可达8.27mm;上库水位提升导致厂区渗流场发生改变,在地质构造发育区域尤为明显,厂区渗流场改变是蓄水期地下厂房围岩变形的主要原因。整体而言,蓄水期白鹤滩左岸地下厂房围岩稳定性良好,可通过扩大错动带C_(2)截流洞长度或加密错动带C_(2)揭穿区域的排水孔的方式来减弱错动带C_(2)渗流对厂房围岩稳定的影响。The Baihetan Hydropower Station is China's second largest hydropower facility.The left bank features complex geological conditions and extensive underground caverns,which have exhibited seepage in the powerhouse area after reservoir impoundment.This seepage significantly influences the deformation and stability of the surrounding rock.This study investigates the stability of the surrounding rock of the underground caverns on the left bank during the reservoir filling process,employing a combination of onsite monitoring data and numerical simulations to analyze the mechanism of how rising reservoir water levels affect the deformation of the surrounding rock.Monitoring data were used to analyze characteristics of the seepage field,such as the underground water free surface,seepage pressure,and leakage quantity,thereby revealing patterns in the deformation and stress trends of the powerhouse surrounding rock.Based on the theory of steady state seepage,the Finite Element Method was used to simulate the left bank seepage field at reservoir levels of 640、775 and 816 m.Furthermore,the Finite Difference numerical simulation software FLAC3D was utilized to study the impact of groundwater seepage on the deformation of the surrounding rock.The comparison between numerical simulations and monitoring results shows a consistent deformation pattern.The findings indicate that during the reservoir impoundment,the deformation of the surrounding rock of the Baihetan left bank powerhouse is positively correlated with the reservoir water level,with rock deformation increasing as the water level rises.The maximum displacement of the upstream rock bench reached 8.27 mm.The rise in reservoir water level led to changes in the seepage field within the powerhouse area,particularly in regions with developed geological structures.These changes in the seepage field during the impoundment period are the primary cause of deformation in the underground powerhouse surrounding rock.Overall,the stability of the surrounding rock of the left bank u

关 键 词：白鹤滩水电站 围岩稳定 渗流 安全监测 数值模拟 

分 类 号：TV731.6[水利工程—水利水电工程] TV223.4