循环爆破作用下锁固型岩质边坡的累积损伤效应及稳定性分析

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中图分类号：0383 国标学科代码：13035 文献标志码：A

Abstract： Thereare many microcracksand micropores in therock，which willinitiate，propagate，and coalescence under dynamic loading，leading torockinstabilityandfailure.Whenblastingexcavationiscariedout，theretainedrockmass willbe subjectedtothedynamic loading generated bycyclic blasting，resulting incumulative damage， which willeadto thereduction the rock mass strength，and even failure. In order to simulate this physical processthe existing rock dynamic damage constitutive model，whichcould perfectlydescribe therock dynamicdamage inducedbyblasting，wasembedded intoFLAC through secondarydevelopment toanalyze thecumulative damage rock massundercyclic blasting.And then it was adopted to simulatethe damage efect and stabilitytherock slope withthe locked segmentundercyclic blasting.The stability the slopeundercyclic blastingwasdeterminedbythedisplacementcriterion method，andthesafetyfactortheslopeaftereach blasting was obtained bythe strengthreductionmethod.Finaly，therelationshipbetween thefailure mode and stability the slopeandthelocation thelockedsegmentwasdiscusedbyanalyzing thedamage，displacementfield，andsafetyfactor the numerical models fordifferent locationsthelocked segment inthest interlayer.Theresultsshowthattheslope stability graduall decreases with increasing the number cyclic blasting after considering the cumulative damage effct therock slope.Fortherockslope withthelockedsegment，thedamagethelockedsegmentfirstlyoccursatbothends，and then propagates tothe middle，inwhich therock massshowsaprogressivefailuremode.Because thecumulativedamage the rock slope is considered，thesafety factor the slope willdecrease after each blasting.When the cumulative damage is not considered，thesafetyfactortheslope is basicallyunchanged.Thefailure mode therock slope withalockedsegment undercyclic blasting is thecombination dynamic tensile failure and shear failure causedbyrock masslip.The location thelocked segment inthe weak interlayer affectsthe failure modeand stabilitytheslope.Therefore，when carlying out similarengineeringactivities，thecumulativedamageefectrockmassshouldbeconsidered toavoidengineeringaccidents.

Keywords： cyclic blasting; accumulative damage; dynamic damage constitutive model; secondarydevelopment; locked segment

自然界中的边坡在受到动荷载作用时往往容易发生滑坡灾害[1-2]。（剩余16749字）