堆积层边坡人工降雨致滑的原位监测试验研究  

In-Situ Monitoring Test Study on Artificial Rainfall Infiltration of a Well-Instrumented Accumulation Slope

作　　者：周中[1] 傅鹤林[1] 刘宝琛[1] 谭捍华[2] 龙万学[2] 周勇[2] 

机构地区：[1]中南大学土木建筑学院,湖南长沙410075 [2]贵州省交通规划勘察设计研究院,贵州贵阳550001

出　　处：《中国铁道科学》2006年第4期11-16,共6页China Railway Science

基　　金：西部交通建设科技项目(2003-318-802-01)

摘　　要：降雨可引起堆积层边坡失稳。为了研究降雨入渗诱发堆积层滑坡的失稳机理以及边坡性状随时间变化的特性，选取贵州晴隆一个典型堆积层边坡进行人工降雨模拟试验和原位综合监测。结果表明：堆积层边坡在降雨入渗影响下多发浅层松弛型破坏，滑动变形区为坡面以下0～4m之内，变形量以坡面最大，从坡面到坡体深部逐渐减小；在实施人工降雨2h，平均入渗率为86%之后，入渗率由于地表径流的增加而随时间逐渐减少，一段时间（6h）之后，入渗率降到一个相对稳定值（50%）；降雨入渗造成土体中孔隙水压力增加，致使边坡土体的抗剪强度由于有效应力的减少及土体吸水软化而降低，降雨入渗的这一双重效应是降雨诱发堆积层边坡失稳的主要原因之一。Rainfall infiltration has a direct effect on the occurrence of accumulation landslide. In order to improve the understanding of the fundamental mechanism of rainfall infiltration induced landslides in accumulation landslide and to clarify some of the important characteristics of slope performance, artificial rainfall simulation tests and in-situ synthetic monitoring method were carried out on a typical accumulation slope in Qinglong, Guizhou province. The monitored results demonstrate that the deformed zone of soil and rock blending landslides caused by rainfall infiltration lies within the top 0-4 m soil layer, where the deformation value of slope surface is the biggest, which gradually reducing from dome to the deep part of slope. The average percentage of infiltration during the first 2 hours is 86%, it reduces gradually with time later because of the increase of the surface runoff. The average percentage of infiltration drops to a relatively stable value （50%） 6 hours later. Rainfall infiltration leads pore-water pressure to increase, which may result in a reduction of shear strength due to a decrease in effective stress and wetting-induced softening. The double effects of rainfall infiltration are the main reasons of rainfall infiltration induced landslides in soil and rock blending slope.

关 键 词：滑坡 堆积层边坡 人工降雨 模拟试验 降雨入渗 原位监测 

分 类 号：TU413.5[建筑科学—岩土工程] TU413.62[建筑科学—土工工程]