【摘要】 四川锦屏二级水电站地处雅砻江中游,流域地形深切狭窄,采用低闸拦截、长引水方案发电,引水隧洞长近17km,最大埋深达2 525 m,地应力高达70 MPa,水压力高达10.2 MPa,其围岩分级方法超越了目前规范标准的应用范畴,现场涌突水、岩爆等地质问题突出。在介绍引水线路地质条件基础上,提取了岩石强度、岩体结构、完整性、高地应力、高外水压力等关键因素,进行影响规律分析,并利用近3年时间连续跟踪、收集的大量地质资料,进行统计分析,归纳各因子的影响权重,建立了适用于锦屏二级水电站高地应力高外水压力条件下的围岩质量快速评价方法,通过现场应用,快速判定的结果与现场类别吻合率均达到88%以上,可为进一步的隧洞地质灾害加固处理提供可靠依据。更多还原

【Abstract】 Jinping Ⅱ hydropower station,located in Yalong river,will generate electricity by employing low gate interception and long-distance diversion,with tunnel length of 17 km,the maximum depth of 2,525 m,the maximum geostress of 70 MPa and water pressure of 10. 2 MPa. Therefore,the surrounding rock classification methods are beyond the present specification standard. Based on the engineering geological background,the key factors influencing the rock classification are extracted,including rock strength,rock structure,integrity,geostress,and high water pressure. Then,in combination with the field statistical data,a rapid assessment method is established for Jinping Ⅱ hydropower station under the high geostress and high water pressure.Field application shows that its prediction accuracy is more than 88%,which can provide a reliable basis for the further reinforcement of tunnel geological disasters.更多还原