黄土边坡降雨入渗规律及其对边坡稳定性的影响  

Rainfall Infiltration Law of Loess Slopes and Its Influence to Slope Stability

作　　者：李国荣[1] 陈文婷[1] 李进芳[1] 朱海丽[1] 胡夏嵩[1,2] 

机构地区：[1]青海大学地质工程系,青海西宁810016 [2]中国科学院 青海盐湖研究所,青海西宁810008

出　　处：《中国水土保持》2014年第8期36-39,69,共4页Soil and Water Conservation in China

基　　金：青海大学中青年科研基金项目(2011-QGY-10;2012-QGY-5);国家自然科学基金资助项目(41162010);国家国际科技合作计划资助项目(2011DFG93160);青藏高原北缘新生代资源环境重点试验室建设项目

摘　　要：以位于青海西宁盆地的某黄土边坡为例,选取较为典型的3次天然降雨,研究了坡体土壤含水量变化和不同降雨历时、降雨强度下的降雨入渗规律,重点分析了降雨入渗对黄土边坡稳定性的影响。结果表明,降雨过程中黄土边坡土壤含水量逐渐增加,降雨结束后随着雨水的继续入渗和蒸发,含水量又逐渐减小;在相同的降雨历时条件下,降雨强度12.50 mm/h时边坡土壤含水量及入渗深度均较降雨强度4.28和0.88 mm/h时大,且坡脚处含水量的增加幅度略大于坡顶;边坡土壤含水量从12.74%增加到27.91%,黏聚力从23.47 kPa降低到9.93 kPa,边坡安全系数从1.67降低到1.31,坡顶和坡脚处的剪应力值分别增大了1.76和17.24 kPa,说明坡脚处应力集中现象与降雨入渗密切相关。The paper selected three typical natural rainfalls,studied the variations of water content and the rainfall infiltration law under the different conditions of rainfall duration and intensity and mainly analyzed the influence of rainfall infiltration to the stability of loess slopes by taking a loess slope of Xi'ning basin in Qinghai as an example. The outcomes show that a) the soil water content increases gradually in the process of rainfall and the water content decreases gradually along with the continuous infiltration and evaporation after the rain; b) under the same conditions of rainfall duration,when the intensity is 12. 50 mm /h,the water content of slope and the depth of infiltration are great comparing with that of rainfall intensity 4. 28 and 0. 88 mm /h and the increase of water content at the foot of slope is slightly greater than that of the top of slope and; c) the water content of slope soil increases from 12. 74% to 27. 91%,the cohesion decreases from 23. 47 kPa to 9. 93 kPa,the safety factor of slope decreases from 1. 67 to 1. 31 and the shear stress value of the foot of slope and the top of slope increases 1. 76 kPa and17. 24 kPa respectively,showing the phenomena of concentrated stress at the foot of slope is closely related to the rainfall infiltration.

关 键 词：降雨入渗 黄土边坡 含水量 安全系数 稳定性 

分 类 号：TU43[建筑科学—岩土工程] TU444[建筑科学—土工工程]