Stability Analysis of Slope with Multiple Sliding Surfaces Basedon Dynamic Strength-Reduction DDA Method

Abstract

The present study aimstoelucidate the problem ofarockmassstructuralplanewitharangeofdamagedegreesandthenumerical model selection for analysis of a slope with multiple sliding surfaces. Based on the relative displacement between blocks, the dynamic strength reduction-discontinuous deformation analysis (hereinafter referred to as DSR-DDA) method is proposed for studyingslopeswithmultipleslidingsurfaces.Theslope-sliderclassiccasewasusedtotestthedisplacementthreshold.Themodel wasappliedtothestabilityanalysisofmultipleslidingsurfacesofahighrockslopeintheFushunWestOpen-PitMine.Theresults showthatwhenthedisplacementthresholdissetto1mm,theerrorbetweentheDSR-DDAresultsandthetheoreticalsolutionis within 0.5%, which satisfies the calculation requirements. The most dangerous slip surface in the Fushun West Open-Pit Mine slope was identified. Based on the numerical slope model after the first landslide, the position of the secondary slip surface was thenidentified.Thefailuremodeistractionslidingfailure,andthemiddleandloweroilshalesplayakeyroleintheslopestability. Thisstudyrecommendsthatminingoftheremainingoilshaleshouldstoptoavoidcausinglarge-scalelandslidesintheupperpart of the slope and landslides at the pit-city boundary.