防渗帷幕与坝基排水孔联合作用下的重力坝深层抗滑稳定性分析

Deep Sliding Stability Analysis of Gravity Dam under Coupling Effect of Grout Curtain and Drainage Holes

针对坝基深层抗滑稳定分析中滑动面上扬压力通常出于安全考虑只在排水孔处折减,未考虑防渗帷幕的防渗减压作用对深层抗滑稳定造成的影响,引入当量长度及附加阻抗概念分析了帷幕与排水孔的减压效果,以及二者联合作用下的减压效果,并将其应用到实际工程中。结果表明,二者联合作用得出的滑动面上扬压力较防渗帷幕与排水孔单独作用更为精确,更贴近工程实际,较好地反映了深层抗滑稳定安全性。

When analyzing the stability against deep layer sliding of concrete gravity dam, for security reasons, people usually considered uplift pressure on slip surface only with reduction in the drainage holes, and ignored the anti-seepage effects, that took an impact on deep sliding stability. With the introduction of the concept of additional resistance and e quivalent length, this paper analyzed the decompression effects of impervious curtain and drainage holes, and considered the decompression effects under the combined effects. By applying it to practical engineering, the results show that the combined effects of both measures can get a more accurate uplift pressure on slid surface than that of a separate effect. Also it is closer to practical engineering, which can better reflect the safety of the stability against deep layer sliding.