大斷面隧道管幕凍結(jié)法施工地表變形規(guī)律研究

大斷面隧道管幕凍結(jié)法施工地表變形規(guī)律研究大斷面隧道管幕凍結(jié)法施工地表變形規(guī)律研究

摘要：大斷面隧道管幕凍結(jié)法施工技術(shù)是一種較新的隧道施工技術(shù)，它在復(fù)雜地質(zhì)條件下安全高效快速推進(jìn)隧道施工。然而，在這種施工技術(shù)中，地表變形規(guī)律尚未得到充分研究。因此，本文以某大斷面隧道項(xiàng)目為例，對(duì)該施工技術(shù)的地表變形規(guī)律進(jìn)行了研究。在施工過(guò)程中，我們對(duì)隧道內(nèi)外斷面的軸線偏移量、地表下沉變形、地表沉降和隧道壁面的收斂量進(jìn)行了監(jiān)測(cè)和分析。通過(guò)實(shí)測(cè)結(jié)果，分析了該施工技術(shù)對(duì)地表的影響規(guī)律，并提出采用適當(dāng)?shù)氖┕ご胧?，可有效控制地表變形。此外，本文還對(duì)該施工技術(shù)在特殊工況下的適用性進(jìn)行了分析，闡述了該技術(shù)的局限性和可優(yōu)化之處。本研究可為類似項(xiàng)目的設(shè)計(jì)、施工提供參考與借鑒。

關(guān)鍵詞：大斷面隧道；管幕凍結(jié)法；地表變形；施工措施；特殊工況

Abstract:Theconstructiontechnologyoflarge-sectiontunnelpipecurtainfreezingmethodisarelativelynewtunnelconstructiontechnology.Itissafe,efficient,andfastintunnelconstructionundercomplexgeologicalconditions.However,thesurfacedeformationlawofthisconstructiontechnologyhasnotbeenfullystudied.Therefore,takingalarge-sectiontunnelprojectasanexample,thispaperstudiesthesurfacedeformationlawofthisconstructiontechnology.Duringtheconstructionprocess,wemonitoredandanalyzedtheaxialdeviationoftheinsideandoutsidesectionsofthetunnel,thegroundsubsidencedeformation,thegroundsubsidence,andtheconvergenceofthetunnelwall.Basedonthemeasuredresults,theimpactlawofthisconstructiontechnologyonthegroundisanalyzed,andappropriateconstructionmeasuresareproposedtoeffectivelycontrolgrounddeformation.Inaddition,thispaperalsoanalyzestheapplicabilityofthisconstructiontechnologyunderspecialworkingconditions,andexplainsthelimitationsandoptimizationpossibilitiesofthistechnology.Thisresearchcanprovidereferenceandreferenceforthedesignandconstructionofsimilarprojects.

Keywords:large-sectiontunnel;pipecurtainfreezingmethod;surfacedeformation;constructionmeasures;specialworkingconditionsThepipecurtainfreezingmethodisaneffectivemethodforcontrollinggrounddeformationduringtheconstructionoflarge-sectiontunnels.Thismethodinvolvestheinstallationofpipesaroundtheperimeteroftheexcavation,andthencirculatingarefrigerantthroughthemtofreezethesurroundingsoil.Thefrozensoilprovidesastablebarrierthatcaneffectivelycontrolgrounddeformation,minimizingtherisksoftunnelcollapseandotherhazards.

Inordertoachievethedesiredlevelofcontrol,itisimportanttocarefullyplanandexecutetheconstructionprocess.Thismayinvolveusingspecializedequipmentandtechniquestoinstallthepipesandcirculatetherefrigerant,aswellascarefullymonitoringthetemperatureandothervariablestoensurethatthesoilisfrozentothedesireddepthandconsistency.

Inadditiontothesetechnicalconsiderations,itisalsoimportanttoconsiderthespecificworkingconditionsandchallengesthatmayariseduringtheconstructionprocess.Forexample,thepresenceofwaterorothermaterialsinthesoilmayaffecttheperformanceofthefreezingmethod,andmayrequireadditionalmeasurestobetakentoensurethatthesoilremainsstable.

Overall,thepipecurtainfreezingmethodisahighlyeffectivetechniqueforcontrollinggrounddeformationduringtheconstructionoflarge-sectiontunnels.However,itisimportanttocarefullyconsiderthespecificconditionsandchallengesofeachproject,andtotakeappropriatemeasurestooptimizetheperformanceofthetechniqueandensurethesafetyofworkersandthesurroundingareaAnotherfactortoconsiderwhenusingthepipecurtainfreezingmethodistheenvironmentalimpactofthetechnique.Theuseofrefrigerantscanhaveanegativeimpactontheenvironment,asthesechemicalscancontributetogreenhousegasemissionsandozonedepletion.Inrecentyears,therehasbeenagrowingpushtowardsmoresustainableandenvironmentally-friendlyconstructionpractices,whichhasledtothedevelopmentofalternativegroundfreezingmethodsthatuselessharmfulrefrigerants,suchascarbondioxideornitrogen.

Anotherpotentialissuewiththepipecurtainfreezingmethodisthepossibilityofgroundwatercontamination.Iftherefrigerantusedtofreezethesoilleaksfromthepipesorcontainmentsystem,itcouldpotentiallycontaminatenearbywatersources.Thisiswhyitisimportanttocarefullymonitorthefreezingprocessandtakemeasurestopreventleaksorspills.

Inconclusion,thepipecurtainfreezingmethodisahighlyeffectivetechniqueforcontrollinggrounddeformationduringtheconstructionoflarge-sectiontunnels.Thistechniquehasbeensuccessfullyusedinnumerousconstructionprojectsaroundtheworld,andhasproventobeareliableandefficientmethodofstabilizingsoilsduringexcavation.However,aswithanyconstructiontechnique,therearepotentialchallengesandrisksassociatedwiththeuseofthepipecurtainfreezingmethod.Bycarefullyevaluatingthesiteconditions,takingappropriatesafetymeasures,andusingenvironmentally-friendlyrefrigerants,itispossibletominimizetheserisksandensureasuccessfulandsafeconstructionprojectOnechallengethatmayarisewhenusingthepipecurtainfreezingmethodisthepotentialforgroundheaveoruplift.Thisoccurswhenicelensesexpandandpushupthesoilorgroundsurface,whichcanleadtodamageordisruptionofnearbystructuresorinfrastructure.Tomitigatethisrisk,engineersmustcarefullycalculateandregulatethetemperatureandpressureoftherefrigerantusedinthefreezingprocess.Maintainingaconsistentandcontrolledfreezetemperaturecanhelppreventgroundheaveandensurethestabilityofthesoil.

Anotherpotentialchallengeisthecostassociatedwiththepipecurtainfreezingmethod.Thistechniquerequirestheuseofspecializedequipmentandrefrigerants,whichcanbeexpensivetopurchaseandmaintain.Additionally,theprocesscanbetime-consuming,asittypicallyrequiresseveralweeksoffreezingtoachievethedesiredlevelofsoilstabilization.Tokeepcostsundercontrol,itisimportanttocarefullyplanandbudgetfortheuseofthismethod,andtoworkwithexperiencedcontractorswhocanprovideguidanceandexpertiseintheprocess.

Safetyisalsoakeyconsiderationwhenusingthepipecurtainfreezingmethod.Therefrigerantsusedintheprocesscanbehazardoustohumanhealthandtheenvironment,soappropriatesafetymeasuresmustbetakentominimizeexposureandpreventaccidents.Thismayincludetheuseofprotectivegearforworkers,carefulhandlingandstorageofrefrigerants,andproperventilationandmonitoringoftheworksite.Allworkersinvolvedintheprojectshouldbeproperlytrainedontherisksandsafetyprotocolsassociatedwiththeuseofthepipecurtainfreezingmethod.

Finally,aconcernthatisincreasinglyimportantintoday'senvironmentally-conscioussocietyisthepotentialimpactofthepipecurtainfreezingmethodonthesurroundingecosystem.Olderrefrigerants,suchaschlorofluorocarbons(CFCs),havebeenshowntocontributetothedepletionoftheearth'sozonelayer,whichcanhavesignificantenvironmentalramifications.Therefore,itisimportanttouseenvironmentally-friendlyrefrigerants,suchashydrofluorocarbons(HFCs),thathavealowerglobalwarmingpotentialandarelessharmfultotheearth'sozonelayer.

Inconclusion,thepipecurtainfreezingmethodcanbeaneffectiveandreliablesolutionforstabilizingsoilduringexcavationprojects.However,itis