Comparative experimental study on deformation and damage characteristics of single coal rock and primary coal-rock combination

Thestudyofthedeformationandfailurelawsintheloadingprocessofcoal-rockcombination samplesareveryimportanttorevealthedynamicmechanismofminedisaster.Inthisstudy,themechanicaldeformationcharacteristicsofprimarycoal-rockcombination,artificialcoal-rockcombination,single coalandsinglerockwereanalyzedandobtainedunderuniaxialloadingconditions.Meanwhile,thedamageandfailurelawsofprimarycoal-rockcombinationwerepreliminarilyexploredbycollectingtheacousticemission(AE)behaviorinformationofsamplesduringloadingprocess.Throughcomparativeanalysis,itisfoundthat:①Theinterfacedifferenceofcoal-rockcombinationhasgreatinfluenceonthe mechanicalandAEcharacteristicsofcoal-rockcombination;②Theorderofuniaxialpeakstrengthof foursamplesis:rock>artificialcoal-rockcombination>primarycoal-rockcombination>coal;③The loadingdeformationandpeakstrengthofthecombinationbodyareinfluencedbymanyfactors,suchas interfaceconditions,elasticmodulusdifferenceofdifferentmediaandsizeeffectofmedia;④Underthe influenceofprimaryinterface,thefracturedevelopmentandpenetrationintheprimarycoal-rockcombinationisrelativelyactiveduringtheloadingyieldfailurestage,andtheearlydamagemainlyoccursin theprimarycoal-rockcombinationorthecoalandrockneartheinterfaceofcombination.