重庆北碚区浸口滑坡形成机制和稳定性分析

Formation mechanism and stability analysis of Jinkou landslide in Beibei District,Chongqing

为研究滑坡形成机制及其稳定特性,以便对滑坡地质灾害进行有效的预测和控制。以重庆北碚区浸口滑坡为例,对滑坡形成条件、滑坡面、滑坡带和影响滑坡稳定性因素进行分析;采用现场大容重试验以及反算法,确定接近工程实际的抗剪强度指标;根据传递系数法对滑坡的稳定性进行了计算和论证。滑坡体地下水的改变使得滑坡土体与滑移带土体抗剪强度降低,滑移带土体软化,静水压力与水浮托力增大,最后致使滑坡体失稳。据计算,该滑坡现状基本稳定,在二十年一遇的暴雨条件下欠稳定。滑坡区有两处致灾体,泥石流现状欠稳定,崩塌堆积体现状基本稳定。在人类工程活动下泥石流和崩塌堆积体均不稳定。

In order to explore the formation mechanism and stability of landslide to forecast and con-trol landslide disaster, Jinkou landslide in Beibei District of Chongqing was studied and its condi-tions and formation mechanism, landslide surface, landslide group and landslide stability factors were analyzed. The shear strength index was calculated by an inverse algorithm and a large bulk density test, and the stability of the landslide was calculated and demonstrated based on the transfer coefficient method. The results indicate that the groundwater of the landslide not only changes the physical and mechanical properties of soil of the landslide group, but also reduces its shear strength, which further leads to soil softening and the increase of hydrostatic pressure and uplift force and fi-nally causes landslide instability. It has been calculated that the current situation of the landslide was stable, and instability and deformation may occur in a case of conditions change in twenty years. The debris flow and the colluvial accumulation are the two disastrous factors to the landslide, and the debris flow was not stable enough in the current situation, while the colluvial accumulation was stable on the whole. The debris flow and the colluvial accumulation would be unstable under hu-man engineering activities.