三峡库区巴东黄土坡巨型古滑坡体形成机理

Formation mechanism of Huangtupo landslide in reservoir of Three Gorges Project

本文采用现场调查、裂隙统计及室内试验相结合的方法,并结合少量钻孔试验,研究了巴东县黄土坡滑坡的边界和深度。研究表明,黄土坡滑坡分为上、中、下三段,是一个巨型古滑坡体。在此基础上,结合宏观地貌特征对该巨型古滑坡体的形成机理进行了分析,认为黄土坡滑坡是分次发生的,中、下段滑坡发生时间较早,且为同时滑动;而上段滑坡则发生时间相对较晚。本文研究成果有助于对黄土坡滑坡的时空稳定性进行预测,以制定相应的防治措施。

The field survey, indoor test and statistic of fractures are combined with boring to investigate the boundary and depth of the Huangtupo landslide located at about 70 km upstream of the Three Gorges Project. It is found that this giant ancient slide body is composed of three sections： the upper, the middle and lower sliding mass. It covers an area of 1.38 km^2 with width of leading edge 1 100m and transverse length 1 780m. Based on the forementioned investigation the method of macroscopic geological feature analysis is applied to study the formation mechanism of the landslide. It is concluded that the formation process of the slide mass can be divided into two stages, the middle and lower sliding mass formed simuhaneously in the earlier stage and the upper one occurred in the latter stage. This result is helpful for forecasting the probable sliding and setups corresponding counter measures.