在倾倒边坡中建设地下调压室的工程地质研究  

Engineering geological study on underground surge chamber construction in toppling slopes

作　　者：黄振伟 茆金柱 蒲进 马力刚 潘坤 HUANG Zhenwei;MAO Jinzhu;PU Jin;MA Ligang;PAN Kun(Changjiang Geotechnical Engineering Co.,Ltd.,Wuhan 430010,China;Changjiang Survey,Planning,Design and Research Co.,Ltd.,Wuhan 430010,China;Tibet Datang Zhala Hydropower Development Co.,Ltd.,Chengdu 610000,China)

机构地区：[1]长江岩土工程有限公司,湖北武汉430010 [2]长江勘测规划设计研究有限责任公司,湖北武汉430010 [3]西藏大唐扎拉水电开发有限公司,四川成都610000

出　　处：《人民长江》2024年第7期130-137,共8页Yangtze River

基　　金：国家重点研发计划项目(2018YFC1505006)。

摘　　要：扎拉水电站调压室建在山体倾倒边坡内,对该边坡及围岩稳定性的系统研究至关重要。根据岩体结构和变形破坏类型的差异,采用岩体结构、岩层转角、风化等定性因素结合波速比定量因素进行综合分区;通过现场超常规原位试验,结合反演计算,综合提出各区适宜的岩体抗剪强度参数;采用数值分析法模拟倾倒边坡变形破坏模式,并通过多种解析法校验边坡稳定性。结果表明:边坡倾倒岩体可分为层状弯曲区、碎裂拉张区、散体坠覆区;厂后倾倒边坡的主要失稳形式为拉裂-滑移-剪断和块体卸荷崩落;在倾倒边坡稳定性评价中,安全系数应取现行技术标准规定范围内的较大值,有利于保障倾倒边坡滑移稳定和坡内洞室围岩变形稳定。研究成果解决了地质条件局限和水工结构要求之间的突出矛盾,在中国水利水电建设中具有开创意义,可为倾倒边坡中工程建设提供参考。The surge chamber of Zhala Hydropower Station is constructed in a toppling slope,so a systematic study on the stability of this slope and surrounding rock mass is crucial.Based on differences in rock mass structure and types of deformation and failure,the in-situ area was divided comprehensively using qualitative factors,such as rock mass structure,bedding angles,and weathering,combined with the quantitative factor of wave velocity ratios.Through unconventional in-situ tests and inversion calculations,suitable shear strength parameters of the rock mass for each zone were proposed.Numerical analysis was used to simulate the deformation and failure modes of the toppling slope,and multiple analytical methods were employed to verify its stability.Results indicated that the toppling rock mass of the slope can be divided into three zones:bedded flexural zone,fractured tensile zone,and loose collapsing zone.The primary failure modes of the plant-rear toppling slope are tensile cracking-sliding-shearing failure and block unloading collapse.In evaluating the stability of the topping slope,the safety factor should be taken to the higher limits of the range specified by current technical standards,which is favorable to ensuring the stability of the toppling slope and the deformation control of rock mass of the cavities.The findings have effectively addressed prominent contradictions between geological conditions and hydraulic structure requirements,and it is pioneering in China's hydropower construction and providing reference for engineering construction in toppling slopes.

关 键 词：倾倒边坡 地下调压室 地质特征 围岩稳定性 原位试验 应力应变数值分析 扎拉水电站 

分 类 号：TV732.5[水利工程—水利水电工程]