摘要
榆林市李家梁水库砂坝自工程蓄水以来存在严重的渗漏安全隐患,为保障工程安全运行,通过水库历史资料数据分析和二维有限元渗流场计算,对该水库砂坝渗流安全及成因进行了深入的分析。结果表明:目前条件下大坝坝体防渗系统虽然满足运行要求,但左岸地下水位高,绕渗情况较严重。大坝左坝肩及坝基多个深度范围内存在中砂夹层以及水坠砂坝施工充填过程中导致坝体颗粒分布不均是造成坝后渗漏的主要原因。根据有限元渗流场计算结果,获得不同部位最大渗透坡降,各计算工况下排水渠底部渗透坡降在0.189~0.241,大于坝基土允许渗透坡降0.125,在库水位升高后,将使下游挟砂渗漏加剧,导致坝体破坏。因此,大坝除险加固需根据计算结果延长渗径,降低下游渗透坡降,保障大坝安全运行。
The sand dam of the Lijialiang Reservoir in Yulin City,Shaanxi,China has been suffered from seepage hazards since the very beginning of impoundment in 2006.To ensure the safe operation of the reservoir,the sandy dam seepage and its causes were analyzed based on reservoir historical data and two-dimensional finite element calculation of the seepage field.The results show that although Hanti-seepage system of the dam body can meet the operational requirements under the current conditions,the groundwater level on the left bank is high and the seepage remains serious.Some gravel-sand interlayers are embedded in the left dam and the dam foundation,and uneven distribution of particles during the filling of the dam construction are the main causes of water leaking.Calculation show that the osmosis slope at the bottom of the drainage channel is 0.189~0.241,which is greater than the allowable value of 0.125,under which the seepage may worsen when water level rises,the downstream shaly sand leakagebe deteriorated,and dam failure may occur consequently.Therefore,the seepage range should be recalculated and extended to reduce the downstream seepage gradient and ensure the safe operation of the dam.
作者
高杰
谈叶飞
张凯
张建飞
GAO Jie;TAN Ye-fei;ZHANG Kai;ZHANG Jian-fei(Shaanxi Provincial Water Resources and River Bank Dispatch Management Center ,Xi’an 718900,China;Nanjing Hydraulic Research Institute,Nanjing 210029,China;State Key Laboratory of Hydrology Water Resources and Hydraulic Engineering,Nanjing 210029,China;Lijialiang Reservoir Management Office,Yulin 719000,China)
出处
《科学技术与工程》
北大核心
2020年第2期797-802,共6页
Science Technology and Engineering
基金
国家重点研发计划(2018YFC1508604)
中央级公益性科研院所基本业务费(Y118015)。
关键词
砂坝
渗流安全
有限元
渗透破坏
李家梁水库
sand dam
seepage safety
finite element
penetration damage
Lijialiang reservoir
