降雨触发关键弱层控制的软岩边坡滑塌机理分析.pdfVIP

56山西水利科技2025年5月

文章编号：1006-8139(2025)02-056-07

降雨触发关键弱层控制的软岩边坡滑塌机理分析

何万通1,2姜晓谋²申晨鹏²丁阔²

（1.水电水利规划设计总院北京100120;2.北方工业大学北京100144）

摘要：当露天采矿边坡存在软弱夹层时，其在降雨作用下的变形破坏机制尤其复杂。文章在现场

地质调查基础上分析了滑塌机理，并通过数值模拟手段，明确了本次滑坡为降雨条件下软弱夹层的蠕变

滑移所引起的上部岩土体牵引式剪切破坏，作为隔水层的软弱泥岩在降雨入渗以及边坡春季解冻的情况

下，含水量持续增大且蠕变作用逐渐加强，对本次滑塌起到控制作用。通过研究在不同降雨条件下边坡

的渗流场、位移场及边坡稳定性的演化发展规律，结果表明当降雨量为50mm/d并持续超过5d或降雨

量为100mm/d并持续超过3d时，坡体内部孔隙水压力及位移将快速增长，边坡迅速失稳并发生滑坡。

关键词：关键弱层；降雨；牵引式滑坡；机理分析

中图分类号：TD32文献标识码：B

AnalysisoftheMechanismofRainfall-InducedCollapseinSoftRockSlopesControlled

byCriticalWeakLayers

HEWan-tongJIANGXiao-mouSHENChen-pengDINGKuo

Abstract:Whenthereareweakinterlayersintheslopeofopen-pitmining,thedeformationandfailure

mechanismunderrainfallisparticularlycomplex.Onthebasisofon-sitegeologicalinvestigation,thelandslide

mechanismwasanalyzed.Byusingnumericalsimulationmethods,itwasdeterminedthatthelandslidewascaused

bythecreepandslidingoftheweakinterlayerunderrainfallconditions,resultinginthetractionshearfailureof

theupperrockandsoilmass.Softmudstone,asanaquitard,continuouslyincreasesitswatercontentandgradually

strengthensitscreepeffectundertheconditionsofrainfallinfiltrationandslopethawinginspring,playinga

decisiveroleinthislandslide.Theevolutionarydevelopmentlawsoftheseepagefield,displacementfield,and

slopestabilityunderdifferentrainfallconditionswereinvestigated.Theresultsshowthatwhentheprecipitationis

50mm/dandlastsformorethan5daysor100mm/dandlastsformorethan3days,theporewaterpressureand

displacementinsidetheslopewillrapidlyincrease,andtheslopewillquicklybecomeunstableandlandslidewi