降雨入渗过程中黄土边坡失稳机理研究  

Study on Instability Mechanism of Loess Slope in the Process of Rainfall Infiltration

作　　者：李锐[1] 陈勇 王青友 LI Rui;CHEN Yong;WANG Qingyou(Yuanping Branch of Shuo-Huang Railway Development Co. Ltd., Xinzhou 036100, China;School of Civil Engineering,Shijiazhuang Tiedao University, Shijiazhuang 050043,China)

机构地区：[1]朔黄铁路发展有限责任公司原平分公司,山西忻州036100 [2]石家庄铁道大学土木工程学院,河北石家庄050043

出　　处：《国防交通工程与技术》2022年第2期15-20,46,共7页Traffic Engineering and Technology for National Defence

基　　金：国家自然科学基金(51978425)。

摘　　要：由于黄土多孔性、强透水性、湿陷性等自身构造特征,降雨入渗是黄土边坡失稳破坏的主要诱发因素。以朔黄铁路山西段K3+0—400 m黄土边坡为研究背景,基于非饱和土理论进行FLAC3D软件的二次开发,利用数值模拟分析了降雨入渗条件下不同降雨强度、不同坡体角度及高度对黄土边坡稳定性的影响,并通过试验验证了数值计算结果的准确性。结果表明:雨水入渗能力随降雨时间及深度的增加而逐渐减弱;雨水入渗深度随降雨强度的增大而增大,但增大幅度很小;降雨强度越大,坡体表层含水量越高;当雨水入渗流速大于土体内部湿润锋出渗流速时,饱和区才会出现;随着坡体角度及高度的增加,坡体发生位移的区域变大;一级边坡坡脚位置为整个坡体的最危险位置。Due to its own structural characteristics,such as porosity,strong water permeability,and collapsibility,rainfall becomes the main inducing factor affecting the destruction of loess slopes.This paper took a section of the loess slope side in section K3+0-400 m of Shuo-Huang Railway located in Shanxi province as a research background,the secondary development of FLAC3D software was carried out based on unsaturated soil theory,the stability of loess slope with different rainfall intensity,different slope angles and heights under the condition of rainfall infiltration was simulated numerically,the accuracy of the numerical results was verified by experiments.The result shows that:rainwater infiltration capacity gradually weakens with increasing rainfall time and depth.With the increase of rainfall intensity,the infiltration depth of rainwater becomes larger,but the increase is small.The greater the rainfall intensity,the higher the surface water content.The saturation zone will appear when the rain water infiltration velocity is greater than the outflow velocity of the wetting front inside the soil.With the increase of slope angle and height,the larger the area of displacement of the slope is.The foot of the first grade slope is the most dangerous position of the whole slope.

关 键 词：黄土边坡 降雨 失稳机理 数值计算 非饱和渗流 

分 类 号：U416.14[交通运输工程—道路与铁道工程]