高速黄土滑坡的一种机理——饱和黄土蠕动液化  

A MECHANISM OF HIGH-SPEED LOESS LANDSLIDES——SATURATED LOESS CREEPING LIQUEFACTION

作　　者：王家鼎[1] 

机构地区：[1]甘肃省科学院地质自然灾害防治研究所

出　　处：《地质论评》1992年第6期532-539,共8页Geological Review

基　　金：甘肃省自然科学基金(编号:ZR-90-01)

摘　　要：本文提出了高速黄土滑坡的一种机理——饱和黄土蠕动液化。文中列举了甘肃地区饱和黄土蠕动液化造成高速滑坡的实例,并从饱和黄土受力前后的应力条件及土体结构内部强度的变化分析了饱和黄土液化的机理。通过现场及室内试验得出剪切强度、剪切速度、饱和度及其它影响因素对液化程度的重要影响。提出了饱和黄土蠕、滑动液化导致高速滑坡的过程。最后,还讨论了高速滑坡及泥流的速度问题。In this paper, the author proposes a mechanism of highspeed loess landslides-saturated loesss creeping liquefaction. A number of examples of Gansu are given andits mechanism is analysed from changes of the inner intensity of loess structure andstress conditions before and after saturated loess is subject to the stress. It is provedby field and laboratory tests that the liquefaction degree of saturated loess is incre-ased with the growth of shearing stres, shearing velocity and degree of saturationand that the initial liquefaction critical value of saturated loess varies from 0.075to 0.13 kgf/cm^2. Because the properties of loess with a saturation degree of morethan 80％ are in keeping with those of loess with 100％ saturation, it is suggestedthat the soil with a saturation degree of more than 80％ is saturated soil. Besides,the author proposes the following process of high--speed landslide trigged by satu-rated loess creeping and sliding liquefaction: irrigation or heavy raining→formationof saturated loess belt→decrease in c and φ values of and formation of slip surfacesin loess bed→creeping of slide body→slight liquefaction→sliding→high--degree lique-faction to complete liquefaction→high--speed sliding→production of mud flow. Final-ly, the velocity of high--speed landslides and mud flow is disscussed.

关 键 词：黄土 滑坡 蠕动 液化 

分 类 号：P642.22[天文地球—工程地质学]