甘肃洒勒山成速滑坡的基本特征及其形成的动力学机制

本文首先讨论了该滑坡的形态、结构和运动的基本特征,指出:(1)该滑坡可分为特点截然不同的两部分。上滑体,可称为滑动铲部分,滑动时此部分滑体主要沿较陡的滑面发生整体性的转动滑移,垂直位移分量较显著。下滑体,可称为碎屑流部分,滑动时此部分滑体基本上呈近水平的运动;(2)主滑面呈上陡下缓渐转水平的座椅状;(3)滑坡的发展具有“推落式”的特点,上滑体是主动部分,它的突然失稳和下滑是推动下滑体运动的主要动力,(4)此滑坡的产生是斜坡变形累进性发展的结果,滑坡后缘拉裂缝的发展经等速开裂、加速开裂和裂缝闭合等三个阶段,最终导致大滑动。文中根据后缘拉裂缝等速开裂的资料,导出了一个预测滑动发生时间的公式。还根据现场证据进一步分析了造成此类滑坡高速远滑的两个机制:滑动铲机制和碎屑流效应,并根据所提出的机制导出了一个预测此类滑坡最大滑速的公式。

ON THE CHARACTERISTICS AND DYNAMICS OF THE CATASTROPHIC MOUNT SALE LANDSLIDE, GANSU (KANSU), CHINA.

The catastrophic landslide occurred on March 7th 1983 in Gansuprovince China is described and its formation mechanism is suggested. The slidmass is composed of two parts the wedge snaped upper part is an active part. Itplayed a role just like a "sliding shovel" and drived the lower passive part tomove with high speed It is illus?rated that the whole process from deformation tofailure is a progressive one and some siages could be recognised the development ofthe tension cracking on the top of the slope may be served as a good example. Itdeveloped through three stages namely steady cracking accelerating cracking andcrackclosing Based on the steady cracking data a formula to predict the t?me oflandslide occurrence is derived Further it is suggested that the "sliding shovel"mechanism and debris flow effect are the main factors which cause the landslide toslide with high speed and for a very long distance.