黑方台黄土泥流滑坡及发生机制研究  

Topographic features and initiation of earth flows on Heifangtai loess plateau

作　　者：武彩霞[1] 许领[1] 戴福初[1] 闵弘[2] 谭国焕[3] 邝国麟[3] 周跃峰[3] 

机构地区：[1]中国科学院地质与地球物理研究所,北京100029 [2]中国科学院武汉岩土力学研究所,武汉430071 [3]香港大学工程学院

出　　处：《岩土力学》2011年第6期1767-1773,共7页Rock and Soil Mechanics

基　　金：香港研究资助局资助(No.7140/08E;No.RGC7140/08E)

摘　　要：黑方台因农业灌溉触发了大量泥流滑坡。为了充分反映黑方台黄土泥流滑坡发育特征,首先基于IKONOS影像对黑方台泥流滑坡进行了遥感解译,随后又开展了详细野外调查工作。结果表明,黄土泥流滑坡呈流态化运移特征,滑距可达300 m以上,是黑方台危害最为严重的一类滑坡。钻探和塬边露头测量显示,研究区黄土底部黏土高程西高东低。地下水数值模拟结果显示,研究区地下水总体上由台塬西部流向地势较低的东部台缘,使得该处地下水抬升幅度要高于西部,从而造成泥流滑坡集中分布于东部台缘。为充分反映该条件下黄土泥流滑坡的破坏机制,开展了室内饱和原状黄土应力路径试验,分析研究了黄土泥流滑坡液化机制。Agricultural irrigation on Heifangtai loess plateau has triggered dozens of loess earth flows.In this paper,IKONOS image was first used to interpret the topographic features of those earth flows,complimented with a detailed field-walk survey.The results indicated that loess earth flows had a travel distance of over 300m,constituting the most destructive threat.The failed material was deposited in a flow-like lobe form.The elevation of the underlying impermeable clay was measured from the outcrops and boreholes,indicating that the eastern part of the plateau was lower than the west.It was observed from groundwater flow modeling that groundwater flow was controlled by the topography of underlying impermeable clay,and converged and partially discharged in the east margin of Heifangtai.This is in coincident with the phenomena that most loess earth flows occurred in the east margin.Laboratory stress path tests were then performed on undisturbed specimens to explain the failure mechanism of loess.The test results show that the initiation of loess earth flow is probably triggered by static liquefaction resulting from rise of groundwater table.

关 键 词：黄土泥流滑坡 农业灌溉 地下水运移模拟 室内力学试验 黑方台 

分 类 号：TD444[矿业工程—矿山机电]