深厚砂砾石覆盖层坝基渗控方案与瞬态坝坡稳定研究

为减少修筑在深厚砂砾石覆盖层上土石坝的渗流损失,提高大坝的安全稳定性,针对某深厚砂砾石覆盖层心墙土石坝,提出一种“库盘水平铺盖+坝基砼垂直防渗墙”空间正交组合渗流控制体系。利用Geo-studio软件耦合Seep/w和Slope/w模块进行坝基渗流方案模拟,基于饱和-非饱和渗流理论研究库水位骤降速率对坝坡瞬态抗滑稳定性的影响。通过对比渗流稳定性态约束条件和经济技术条件,提出坝基渗控最优方案。研究表明,“库盘水平铺盖+坝基垂直砼防渗墙”空间正交组合渗流控制体系在技术经济方面优势显著,可为类似坝基条件下土石坝渗流控制和安全调度运行提供一定的技术参考。

Dam foundation seepage control scheme and transient dam slope stability on deep gravel overburden

In order to reduce the seepage loss and improve the safety and stability of the earth-rock dam with deep gravel overburden, a spatial orthogonal combination seepage control system of "horizontal pallet covering and dam foundation vertical concrete cutoff wall" was proposed for a core wall embankment dam. The Seep/w and Slope/w modules of Geo-studio software were coupled to simulate the dam foundation Seepage control schemes. The influence of reservoir water level sudden drop rate on transient anti-sliding stability of dam slope was studied based on the saturated-unsaturated seepage theory. Finally, optimal seepage control scheme was proposed by comparing the seepage stability state constraints,economic and technical conditions. The results show that the spatial orthogonal combination seepage control system has obvious advantages in terms of technology and economy, which can provide a certain technical reference for seepage control and safe operation of earth-rock dams with similar dam foundation conditions.