Numerical simulation on stability of right bank slope of Longpan in Tiger-Leaping gorge area

Abstract

The stability of the right bank slope of Longpan in Tiger-Leaping Gorge area is important to the building of the Tiger-Leaping Gorge reservoir. So it is important to select a proper method to obtain correct results. With the development of the calculations techniques, especially with the development of nonlinear mechanics of the rock and soil materials, the strength reduction FEM emerged as required. In the strength reduction FEM, it was not necessary to know where the slip surface was, and the initial geostatic stress could be included in the analysis which was more advantageous than the limited equilibrium method. The strength reduction FEM was used to study the stability of the right bank slope of Longpan in Tiger-Leaping Gorge area, and the stability coefficient of the slope under current stress state, the potential failure surface and its failure model. As a comparison, DEM analysis of the slope was executed. It was indicated that there was basic consistency between the results of the strength reduction FEM and DEM, which ensured the reliability of the result.

虎跳峽龍蟠右岸邊坡的穩定性問題對擬建的虎跳峽水電站具有重要的意義。在鉆探及平硐勘查過程中尚未發現該邊坡有連續的滑動面,因此無法用傳統的極限平衡法對其穩定性作出判定。本文運用有限元強度折減法對虎跳峽龍蟠右岸邊坡的穩定性進行了穩定性分析研究,得出該邊坡在現今應力場狀態下的穩定性問題、潛在的破壞模式及相應的滑動面。此外,還結合離散元模擬進行了對比,結果表明有限元強度折減法和離散元方法獲得的滑動面基本一致,增強了計算結果的可靠性。