黄河茨哈峡导流洞进口边坡稳定性综合评价及处置优化  

Comprehensive Evaluation and Disposal Optimization of Slope Stability at the Entrance of Cihaxia Diversion Tunnel on the Yellow River

作　　者：许建军 周恒[2] 高乔裕 刘世隆 段军邦 张峰华 XU Jian-jun;ZHOU Heng;GAO Qiao-yu;LIU Shi-long;DUAN Jun-bang;ZHANG Feng-hua(Huanghe Hydropower Development Corporation Limited,Xining 810000,Qinghai Province,China;Northwest Engineering Corporation Limited,Xi'an 710065,Shaanxi Province,China;State Key Laboratory of Water Resources Engineering and Management,Wuhan University,Wuhan 430072,Hubei Province,China)

机构地区：[1]青海黄河上游水电开发有限责任公司,青海西宁810000 [2]中国电建集团西北勘测设计研究院有限公司,陕西西安710065 [3]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》2024年第6期231-238,共8页China Rural Water and Hydropower

摘　　要：复杂地质条件下边坡稳定性受结构面、岩体性质等因素影响明显,其准确评价对边坡施工安全至关重要。依托黄河茨哈峡导流洞进口边坡施工工程,提出了一套综合赤平投影理论、二维极限平衡法与三维极限平衡法的边坡稳定性综合评价方法。首先基于赤平投影理论定性地描述了具有复杂结构面的导流洞进口边坡4#倾倒体失稳块体;随后分别采用二维极限平衡法与三维极限平衡法对施工期逐层开挖过程诱发边坡失稳风险进行了分析;最后根据“少开挖+强支护”的设计原则,从多方法综合评价和循环优化的角度,提出将原破碎体全部挖除的大开挖方案优化为保留部分破碎体的小开挖方案,并从安全性与经济性的角度对优化方案进行了评价。计算结果表明大开挖方案边坡稳定性安全系数约为1.17~1.19,小开挖方案安全系数约为1.078,大开挖方案边坡安全性高于小开挖方案;在对小开挖方案进行支护优化后边坡稳定性安全系数提高至1.159~1.183,边坡稳定性由临界稳定变为稳定,支护优化效果显著。综合边坡开挖安全性与经济性评价结果可见,所提“少开挖+强支护”边坡开挖方案符合相关规范安全控制标准,具有较好的经济效益与工程价值,可为相关工程提供参考。The stability of slopes under complex geological conditions is obviously affected by factors such as structural plane and rock mass properties,and its accurate evaluation is very important for the safety of slope construction.Based on the construction project of the inlet slope of the diversion tunnel of the Cihaxia of the Yellow River,this paper proposes a comprehensive evaluation method of slope stability based on the stereographic projection theory,the two-dimensional limit equilibrium and the three-dimensional limit equilibrium method.Firstly,based on the stereographic projection theory,the unstable block of slope 4#toppling body with complex structural plane is qualitatively described.Then,the two-dimensional limit equilibrium and three-dimensional limit equilibrium methods are used to analyze the risk of slope instability induced by layer-by-layer excavation during construction.Finally,from the perspective of multi-method comprehensive evaluation and cyclic optimization,a targeted support optimization scheme is proposed according to the design principle of'less excavation+strong support',and the optimization scheme is evaluated from the perspective of safety and economy.The calculation results show that the slope stability safety factor of the large excavation scheme is about 1.17~1.19,and the safety factor of the small excavation scheme is about 1.078.The slope safety of the large excavation scheme is higher than that of the small excavation scheme.After the support optimization of the small excavation scheme,the safety factor of the slope stability increased to 1.159~1.183,the slope stability changed from critical stability to stability,and the support optimization effect is remarkable.Based on the safety and economic evaluation of slope excavation,it can be seen that the proposed'less excavation+strong support'optimization scheme meets the safety control standards of slope excavation related specifications,and has good economic benefits and engineering value,which can provide reference for related projec

关 键 词：边坡稳定性 赤平投影法 极限平衡分析法 支护措施优化 

分 类 号：TV67[水利工程—水利水电工程]