小湾水电站高水位运行下拱坝和坝肩边坡稳定性分析

Stability analysis on arch dam and abutment slopes of Xiaowan Hydropower Station during operation under high water level

基于卸荷岩体力学理论和方法,采用大型岩土工程数值分析软件(FLAC3D),对小湾水电站高水位运行大坝与边坡相互作用进行了研究,建立了其坝肩边坡和拱坝三维有限元模型。根据施工过程,在初始工况、开挖工况、卸荷工况、加固工况基础上,考虑了正常蓄水位情况时拱端推力、坝肩边坡的应力和位移变化规律,并与其监测值进行了对比。结果表明计算值与监测值十分吻合,论证了坝体设计的合理性,为小湾水电站高水位安全运营提供了一定的参考依据。

Based on the method and theory of unloading rock mass mechanics,the interaction between both the dam of Xiaowan Hydrpower Station and its slopes during the operation under high water level is studied herein with the large geotechnical numerical analysis software(FLAC3D,i.e.Fast Lagrangian Analysis of Continua in 3Dimensions),and then a 3-D finite element model of the arch dam and abutment slopes is established.In accordance with the construction process,the thrust at springer,the stress and displacement changing law of the abutment slopes under the normal water storage level are considered on the basis of the initial condition,excavation condition,unloading condition,strengthening condition,furthermore,compared with the monitoring values concerned.The results show that not only the calculated values coincide closely with those from the monitoring,but the rationality of the dam design is also demonstrated;which provide a certain reference for the operation of the hydropower station under a high water level.