摘要
伴随西部地区水电工程的蓬勃建设,水电站建成投运改变了岸坡原始的地质条件,库水位变化引起岸坡内动水压力与静水压力的变化,从而影响岸坡的稳定性。以往水库蓄水对岸坡作用往往通过野外地质调查及相应的工程地质分析进行,缺乏蓄水前与蓄水后的定量对比分析。采用多源信息观测手段,分析大渡河流域黄草坪变形体蓄水前、初蓄期及正常运行期各阶段斜坡变形破坏特征。研究成果表明:①黄草坪变形体为一处砂页岩倾倒变形体,并将变形体区域分为强变形Ⅰ区、弱变形Ⅱ、Ⅲ区;②黄草坪变形体于2015年10月水库蓄水后开始变形,Ⅰ区变形显著,每年汛期加剧变形,而汛期后监测点曲线变形速率减小,且库水位下降的历时曲线与变形曲线的波峰基本对应,但由于地下水相对库水下降滞后性,变形曲线的波峰相对汛期库水位下降的历时曲线有所延后。③黄草坪变形体的形成可概括为岩卸荷—倾倒变形发展阶段;垂直层面的张裂隙扩展阶段;蓄水过程坡前水位抬升,局部裂隙贯通破坏阶段;水库运行过程中坡体宏观变形破坏阶段。本文研究成果可对类似水电工程地质灾害防治具有指导意义。
With the vigorous construction of hydropower projects in the western region, the completion and operation of hydropower stations have changed the original geological conditions of the bank slope. In the past, the effect of reservoir water storage on the bank slope was usually carried out through field geological survey and corresponding engineering geological analysis, and there was a lack of quantitative comparative analysis before and after water storage. The multi-source information observation method was used to analyze the slope deformation and failure characteristics of the Huangcaoping landslide in the Dadu River Basin before water storage, the initial storage period and the normal operation period. The research results show these as follows. The Huangcaoping landslide is a sand sheet Rock dumping deformation body, and the deformation body area is divided into strong deformation zone I, weak deformation zone II, and III. The Huangcaoping deformed body began to deform after the reservoir was impounded in October 2015. The deformation of zone I was significant, and the deformation was exacerbated during the flood season every year. However, due to the hysteresis of the decline of groundwater relative to the reservoir water, the peak of the deformation curve is delayed relative to the duration curve of the reservoir water level decline in the flood season. The formation of huangcaoping landslide can be summarized as: Unloading and toppling defor-mation development stage of rock mass. The extension stage of the tensile fracture in the vertical plane;In the process of impoundment, the water level in front of the slope rises and local cracks break through. Macro deformation and failure stage of slope during the operation of reservoir. The research results can have guiding significance for the prevention and control of geological disasters in similar hydropower projects.
作者
黄会宝
何朝阳
巨淑君
段亮
罗浩
解明礼
HUANG Hui-bao;HE Chao-yang;JU Shu-jun;DUAN Liang;LUO Hao;XIE Ming-li(Guoneng Dadu River Hydropower Co.,Ltd.,Chengdu 610093,China;College of Water Resource&Hydropower,Sichuan University,Chengdu 610065,China;State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu 610059,China;Tianjin Municipal Engineering Design&Research Institute,Tianjin 300051,China)
出处
《科学技术与工程》
北大核心
2022年第27期12139-12149,共11页
Science Technology and Engineering
关键词
库岸边坡
多源数据融合
现场调查
INSAR
专业监测
bank slope
multi-source data fusion
site investigation
InSAR
professional monitoring
