关键词: 软弱夹层, 工程地质分析, 空间解析几何法, 极限平衡法, 滑动面反演, 强度折减法

Abstract: The determination of the sliding surface is the key problem in slope treatment， but the traditional explorationtechnology in the process of sliding surface survey and identification often exists time-consuming， labor-consuming， damage to the slope， with security risks and other issues. To overcome the limitation of traditional sliding surface determination method， taking the high slope with gently-inclined soft interlayers of Huangshan Limestone Mine in Sichuan as an example， under the condition of emergency treatment of slope ， based on the comprehensive application of engineering geological analysis， space analytic geometric method， limit equilibrium method and strength reduction method， ainversion method of sliding surface was proposed， which takes engineering geological analysis method as the premise， spatial analytic geometry method and limit equilibrium method as the calculation and analysis means， and strength reduction method as the inspection guarantee. Firstly， the overall and local failure modes of the slope were determined according to engineering geological analysis. Secondly， the spatial morphology of the sliding surface at theforward and backward edges of the slope was determined by using the spatial analytical geometry method. Finally， the stability coefficient of the slope was calculated repeatedly by using the limit equilibrium method， and the specific position of the sliding surface was determined， and the sliding surface inversion results were verified by the finite element shear strength reduction method. The slope slides along the soft interlayers as a whole， and the forward and back edges were arc-shaped sliding failure. The results showed that the sliding surface was located at a position with a vertical distance of 26 m from the platform of 775 m to the soft interlayers. The slope stability coefficient calculated by finite element method shear strength reduction method is 1.00， and the feasibility and correctness of this method was proved. The above results provided a new idea for determining sliding surface and has certain reference significance for rapid identification and determination of similar slope sliding surface and emergency treatment of dangerous rock mass.

Key words: gently-inclined soft interlayers, engineering geological analysis, space analytic geometry, limit equilibrium method, inversion analysis of sliding surface, strength reduction method