隔离边界条件下连续降雨诱发黄土边坡开裂试验研究  

Experimental Study on Loess Slope Cracking Induced by Continuous Rainfall Under Isolated Boundary

作　　者：王磊 李荣建[1] 潘俊义[3] 刘军定 杨强[1,4] Wang Lei;Li Rongjian;Pan Junyi;Liu Junding;Yang Qiang(Institute of Geotechnical Engineering,Xi’an University of Technology,Xi’an 710048,China;Architectural Engineering Institute,Yan’an University,Yan’an 716000,China;Xi’an Changqing Technology and Engineering Co.,Ltd.,Xi’an 710018,China;Center for Hydrogeology and Environmental Geology,CGS,Baoding 0711051,China)

机构地区：[1]西安理工大学岩土工程研究所,西安710048 [2]延安大学建筑工程学院,延安716000 [3]西安长庆科技工程有限责任公司,西安710018 [4]中国地质调查局水文地质环境地质调查中心,保定071051

出　　处：《天津大学学报（自然科学与工程技术版）》2019年第11期1163-1170,共8页Journal of Tianjin University：Science and Technology

基　　金：国家自然科学基金资助项目(41877278,51768073,51808479,41472296);陕西省黄土力学与工程重点实验室项目(14JS064);陕西省教育厅专项科研项目(18JK0880);综合地质调查项目(DD20190268)~~

摘　　要：为了对连续降雨诱发黄土边坡破坏过程有更直接深入的认识,在陕北大型均质黄土边坡设置隔离边界并开展人工模拟降雨现场试验.总结了边坡开裂破坏特征,分析了坡顶裂缝及坡体破坏过程的力学机制,研究了水分入渗以及隔离边界对边坡开裂破坏的影响.结果表明:降雨侵蚀及雨水径流是坡顶土体开裂的必要条件,边坡浅层土体产生的竖直拉张裂缝及深层土体的剪切破坏倾斜裂缝贯通至坡面,坡体最终呈“L”型开裂面,坡顶的开裂宽度与开裂深度的发展变化趋势呈现一定相关性;降雨期间坡顶部位较易触发一定规模的浅层滑坡,降雨结束后水分下渗可能引发边坡深层破坏;隔离槽对降雨边界的物理隔离和阻断效应导致坡顶呈“一”型开裂线,并且边界土体-隔离布薄弱区裂缝剧烈发育扩展,易导致边坡更大规模破坏.An isolated boundary was established and a large homogeneous loess slope in northern Shaanxi was subjected to an artificial simulated rainfall field test to obtain a direct and in-depth understanding of loess slope failure induced by continuous rainfall.The characteristics of slope cracking failure were summarized.Then,the mechanical mechanism of cracking and failure was analyzed,and the influences of water infiltration and isolated boundary cracking failure were studied.Results showed that rainfall erosion and runoff were the necessary conditions for slope top-soil cracking.Tensile cracks in shallow soil and shear-failure cracks in deep soil penetrated the slope surface.The slope cracking surface presented an “L” shape.The developmental trends of crack width and depth were correlated.Shallow landslides may be triggered during rainfall.Then,water infiltration may cause deep failure.The crack line exhibited a“一”shape under the physical isolation and blocking effect of the isolation groove.The rapid development of cracks in the soil-isolation cloth in the weak boundary area may initiate a larger scale disaster.

关 键 词：黄土边坡 连续降雨 现场试验 隔离边界 开裂破坏 

分 类 号：TU43[建筑科学—岩土工程]