穿軟硬互層隧道圍巖變形破壞模擬研究摘要：隧道工程一直是地下工程中重要的組成部分，而圍巖變形破壞是隧道工程中常見的安全問題。本文通過軟硬互層隧道圍巖變形破壞模擬研究，探討其變形破壞機理。先采用FLAC3D有限差分法模擬軟硬互層構(gòu)造隧道及其變形破壞特征，并驗證模擬結(jié)果與現(xiàn)場實測數(shù)據(jù)進行對比。其次研究了圍巖軟硬互層變形破壞機理，建立了圍巖軟硬互層及其與支護體系之間的相互作用模型。在此基礎(chǔ)上，本文研究了軟硬互層構(gòu)造隧道圍巖變形破壞特征，分析了變形破壞的形成機制。結(jié)果表明，軟硬互層隧道圍巖變形破壞主要表現(xiàn)為切向位移和軸向應(yīng)變。同時，隧道圍巖變形破壞與軟硬互層之間的相互作用密切相關(guān)，通過優(yōu)化隧道支護體系、提高圍巖控制技術(shù)和研究隧道圍巖變形破壞機理等手段，可以有效減少隧道變形破壞的發(fā)生。

關(guān)鍵詞：隧道工程；軟硬互層；圍巖變形破壞；FLAC3D有限差分法；支護體系；變形破壞機理

Abstract:Tunnelengineeringhasalwaysbeenanimportantpartofundergroundengineering,androckdeformationandfailurearecommonsafetyproblemsintunnelengineering.Inthispaper,throughthesimulationstudyofdeformationandfailureofthesoft-hardinterlayertunnel,thedeformationandfailuremechanismisexplored.Firstly,theFLAC3Dfinitedifferencemethodisusedtosimulatethesoft-hardinterlayerstructuretunnelanditsdeformationandfailurecharacteristics,andthesimulationresultsareverifiedbycomparisonwithfieldmeasureddata.Secondly,themechanismofsoft-hardinterlayerdeformationandfailureofsurroundingrockisstudied,andtheinteractionmodelbetweenthesoft-hardinterlayerandthesupportsystemisestablished.Onthisbasis,thedeformationandfailurecharacteristicsofthesoft-hardinterlayerstructuretunnelsurroundingrockarestudied,andthemechanismofdeformationandfailureformationisanalyzed.Theresultsshowthatthedeformationandfailureofthesoft-hardinterlayertunnelsurroundingrockismainlymanifestedastangentialdisplacementandaxialstrain.Atthesametime,thedeformationandfailureoftunnelsurroundingrockiscloselyrelatedtotheinteractionbetweenthesoft-hardinterlayer.Byoptimizingthetunnelsupportsystem,improvingrockcontroltechnology,andstudyingthedeformationandfailuremechanismoftunnelsurroundingrock,theoccurrenceoftunneldeformationandfailurecanbeeffectivelyreduced.

Keywords:Tunnelengineering;soft-hardinterlayer;rockdeformationandfailure;FLAC3Dfinitedifferencemethod;supportsystem;deformationandfailuremechanismInordertostudythedeformationandfailuremechanismoftunnelsurroundingrock,theFLAC3Dfinitedifferencemethodcanbeused.Thismethodcansimulatethedeformationandfailureprocessoftunnelsurroundingrockunderdifferentworkingconditions,whichcanprovideatheoreticalbasisforthedesignandconstructionoftunnelengineering.

Inaddition,theoptimizationofthetunnelsupportsystemcaneffectivelycontrolthedeformationandfailureoftunnelsurroundingrock.Thesupportsystemshouldbeselectedbasedonthecharacteristicsofthesoft-hardinterlayer,andappropriatemeasurescanbetakentopreventinstabilityandcollapseofthesurroundingrock.

Moreover,theimprovementofrockcontroltechnologyisessentialforthesafetyandstabilityoftunnelengineering.Strengtheningthemonitoringandearlywarningsystem,usingadvancedrockreinforcementmaterials,andadoptingeffectivegroutingtechniquescaneffectivelycontrolthedeformationandfailureoftunnelsurroundingrock.

Therefore,thestudyofthesoft-hardinterlayerandthedeformationandfailuremechanismoftunnelsurroundingrockisofgreatsignificanceforthesafeandstableconstructionoftunnelengineering.Throughthecomprehensiveuseofthesemethodsandtechniques,theoccurrenceoftunneldeformationandfailurecanbeeffectivelyreduced,ensuringthesafetyandstabilityoftunnelengineeringprojectsInrecentyears,theapplicationofsupportingtechnologiessuchasgroutingandanchoringhasbecomeincreasinglymatureintunnelengineering.Groutingtechnologycanimprovethesurroundingrockmassqualityandreducethepermeabilityoftherockmassaroundthetunnel.Atthesametime,rockboltscanreinforcethestabilityofthesurroundingrock,butthesemethodshavelimitations.

Inordertofurtherensurethesafetyandstabilityoftunnelengineering,itisnecessarytoexploreothereffectivemethods.Oneofthemethodsistheuseoffiber-reinforcedpolymer(FRP)compositematerialtoreinforcethesoft-hardinterlayeroftunnelsurroundingrock.FRPhastheadvantagesofhighstrength,goodcorrosionresistance,lightweight,andeasyconstruction.TheuseofFRPcaneffectivelyimprovethestrengthandstiffnessofthesoft-hardinterlayer,resistdeformationandfailure,andreducetheoccurrenceoftunnelcollapse.

Anothereffectivemethodistostrengthenthedrainagecapacityofthetunnel.Theimproperdrainageofwaterinthetunnelisoneofthemainfactorsleadingtothedeformationandfailureofthesurroundingrockofthetunnel.Installingdrainageequipmentinthetunnelcaneffectivelydischargewaterinatimelymanner,reducewaterseepageintherockmass,andavoidthedamagecausedbywaterpressuretothesurroundingrock.

Inaddition,theapplicationofmonitoringandearlywarningsystemsisalsoofgreatsignificanceforthesafeandstableconstructionoftunnelengineering.Byinstallingvarioussensorsinthetunnel,suchasinclinometers,settlementgauges,andstraingauges,thedeformationandfailureofthesurroundingrockcanbemonitoredinrealtime.Ifthedeformationexceedsthesetvalue,itcantriggeranearlywarningsystemtoalerttheconstructionpersonneltotaketimelymeasurestodealwithit.

Overall,thesafeandstableconstructionoftunnelengineeringrequiresthecomprehensiveuseofvariousmethodsandtechnologies,includingstrengtheningthesoft-hardinterlayer,improvingthedrainagecapacityofthetunnel,andinstallingmonitoringandearlywarningsystems.Withtheuseofthesemethods,thedeformationandfailureoftunnelsurroundingrockcanbeeffectivelycontrolled,ensuringthesafeandstableconstructionoftunnelengineeringprojectsInadditiontotheaforementionedmethods,thereareseveralothertechniquesthatarecommonlyusedintunnelengineeringtoensuresafeandstableconstruction.Theseincludegrouting,shotcreting,blastprotectionmeasures,andgroundfreezing.

Groutingisamethodofinjectingaliquidorslurrymixtureintothesurroundingrocktofillincracksandvoids,creatingamorestablegroundstructure.Thistechniqueiscommonlyusedinsoftgroundconditionsorareaswithhighwatertables.Thegroutmixturemayconsistofcement,sand,andwaterormaybeachemicalsolutiondependingonthespecificconditionsofthesite.

Shotcretinginvolvessprayingaconcretemixontothetunnelwallstocreateareinforcedlayerofconcrete.Thistechniqueiscommonlyusedintunnelswithunstableorweakrockformations.Shotcreteprovidesimmediatesupporttotheexcavationandhelpspreventfurtherdeformationofthesurroundingrock.

Blastprotectionmeasuresinvolveusingshieldingstructuresorbarrierstoprotectnearbystructuresandpersonnelfrompotentialblastdamageduringconstruction.Thesemeasuresarecriticalinareaswithdensepopulationsorbuildingsthatcouldbeaffectedbytheshockwavesgeneratedduringblasting.

Groundfreezingisatechniqueusedinareaswithhighwatertablesorunstablesoilconditions.Thismethodinvolvesdrillingaseriesoffreezepipesintothegroundandcirculatingrefrigerantthroughthemtofreezethesurroundingsoil.Thiscreatesastablebarrierthatpreventsgroundwaterfromenteringtheexcavationsite,allowingforsafeandstableconstruction.

Inconclusion,thesafeandstableconstructionoftunnelengineeringprojectsrequiresacomprehensiveapproachthatintegratesvariousmethodsandtechnologies.Thesemethodsincludesoft-hardinterlayerstrength