土木工程垃圾填埋场中英文对照外文翻译文献.docx

土木工程垃圾填埋场中英文对照外文翻译文献.docx

《土木工程垃圾填埋场中英文对照外文翻译文献.docx》由会员分享，可在线阅读，更多相关《土木工程垃圾填埋场中英文对照外文翻译文献.docx（24页珍藏版）》请在冰点文库上搜索。

土木工程垃圾填埋场中英文对照外文翻译文献

中英文资料翻译

（文档含英文原文和中文翻译）

SeveralMotivestoBringtheResearchonLandfillCapCoverstotheStandardoftheResearchersaboutBottomLiners

ABSTRACT:

Thebehaviorofthecapbarrier（andmainlythesealinglayer）inthecentralareaofalandfillwheretheslopeislow,isconsidered.Themainregulationsaboutlandfillsareconcentratedinthepresenttimeontherequirementsrelatedtothebottombarrier.Thecapbarrierhasalsoafundamentalfunction（tolimitortocontrolthehumidityoftheconfinedwaste）.ItisshowninthisLecture,whichissupportedbythepresentationofsomeexperimentalresearches,thatmeetingthistargetisreallyabigchallengeandalsoanimportantecologicalchallengesincelandfillsareanimportantspringofmethane,potentgreenhousegas.Firstandforemostanin-depthresearchonthebehavioroftheconfinedwasteisnecessarytodemonstratethetechnicalinterestofgeosyntheticsolutionsandalsotodevisenewgeosyntheticsystems.

KEYWORDS:

landfill,waste,biodegradation,greenhousegas,settlement

INTRODUCTION

Firstly,it’sworthnotingthatlandfillsshouldbeconsideredasamoderntechniqueoftreatmentofwaste,whichwasmovinganddevelopingsignificantlyduringthelastdecade.Themainregulationsaboutlandfillsareconcentratedinthepresenttimeontherequirementsrelatedtothebottombarrier.Thecapbarrierhasalsoafundamentalfunction（tolimitortocontrolthehumidityoftheconfinedwaste）.Tocoverwithanefficientcapbarrierawastedisposalisakeyissue.

InapreviousKeynoteLecture（Gourc,2004）,theglobalproblemofstabilityofgeosyntheticscompositesystemsusedascapbarriersonsteepslopesoflandfillswereconsidered（Gourcetal,2008）.

InthepresentLecture,thebehaviorofthecap（andmainlythesealingliner）inthecentralareaofalandfillisconsidered.Itisdemonstratedthatanin-depthknowledgeofthewastebehaviorisrequiredbeforetooptimizetheconceptoftheliner.Geosyntheticssolutionsareveryoftenbetterthanminerallayers;inmanycasesthesegeosyntheticssolutionshavealreadyprovedtheirworth,butnewapplicationsarestillpossible.Theapplicationofgeosyntheticstocapoverofnewlandfillsbutalsoofolduncontrolleddumpsisapromisingmarket.

CAPCOVERREQIREMENTS

TheFrenchregulationdoesnotcompletelyspecifythestructureofthecapcover（DecreeSept.1997）andrecommendonlytwoconceptsaccordingtothenatureofwaste（Fig.1）:

-forMunicipalSolidWaste（MSW）,withabiodegradablepart,thecovermustbeprovided“withasemi-permeablelayerinnaturalfinesoilcompactedonathicknessofatleast1meter,oranyequivalentdeviceensuringthesameeffectiveness.”

-forHazardouswaste,itmustbeprovided“withanimpermeablelayerof1metercharacterizedbyanhydraulicconductivitylowerthan1.10-9m/sassociatedatageomembraneoranyequivalentdevice.”

Indeedthisregulationdoesnotmeetthemanyconcernsrelatedtothebehaviorofalandfillcapcoverundercomplexsolicitations.

STORAGEOFHAZARDOUSWASTE

Landfillforthistypeofwasteincludesgenerally,followingregulationsinmanycountries,acapcoverwithacompactedclayliner（CCL）.Imperviousnessofclayisessentialtosafeguardthehazardouswastesagainstwetting,inordertopreventleachingandwashingofthewasteandconsequentlypossiblepollutionofthegroundwaterincaseoffilingofthebottombarrier.HowevertheCCLmeetsmanyproblems,inparticularthoserelatedtoitsmechanicalsolicitationsafterclosingthecell,specificallydifferentialsettlements.

SomeexperiencescarriedoutinFrancewhichdemonstratethesensitivityofCCLtocrackingincaseofbendingsolicitationarepresented:

Behaviorofaclaylayersubjectedtoasinkholesituation.

Testprocedure

TheexperimentswereperformedontheCEREDsite（Suez）（Fig.2）onclaymaterialwithalargeproportionofcoarsesoil（materialconventionallyusedinFranceforwastelandfillsites）.

TheCCL（Aupiconetal,2002）iscompactedonacavityof（2m×2m）filledwithexpandedclaybeads.Inasecondstage,theclaybeadsareremoved,simulatingaconcentratedsubsidenceofthewaste.Thisconditionisspecificallyseverebutmaycorrespondtorealisticsituationforinstanceincaseofinternalcollapsingorburningofapieceofwaste.

Twoconditionswereconsidered:

-Thefirstonewasalayerofunreinforcedclay,thicknessHreducedto0.6m,aboveasinkholewithaspanofalengthLof2meters.

-Thesecondonewasalayerofthesameclay,thicknessHreducedto0.6m,reinforcedatthebasebyageosyntheticsheet,（Fig.2）.Thetensilestiffnessofthesyntheticsheet（overalllengthof8m）isJ=1818kN/m.Theanchorageofthesheet（freeends）isobtainedbyfriction（noslidingobservedattheedges）.

Theverticaldeflection（f）isrecordedateverystageoftheexperience.

Layerofreinforcedclay

Duringthefirststep（theprocessofemptyingofthecavity）,adetachingisobservedbetweentheloweranduppersub-layersofclay,revealingcracksinclinedtowardstheedgesofthecavity（Fig.2and3）correspondingtothecompactionintwostages.Thepoorinterlockingbetweentwocompactedlayersisaclassicalfaultanditwasfinallyinterestingevenifitwasunintentional.Consequentlythelowersub-layerbehavedindependentlylikea0.3mlayersubjectedtobendingunderitsownweight.Thegeotextilefollowedthedeformationofthelowersub-layerbutwasnotverysollicitated:

themaximumverticaldisplacementofthelowersub-layerbeingstillsmall（f=10mm）.Theuppersub-layerdidnotdeformsignificantlyunderitsownweightanditcouldbeconsideredthatwaterandgastightnesswerekeptsatisfactoryforthislayer.

Inasecondstep,anoverloadwasputatthesurfaceinordertoincreasethebendingdeformationofthestructure（Fig.4）.Finallyasitwasimpossibletoobtainashorttermcollapseofthestructure,thelongtermdeflectionwasmonitoredunderaconstantoverload（q）forseveralmonths.Anincreaseinverticaldeflection（creep+anchorageslip）oftheclayandgeosyntheticlinerwasobserved.Theevolutionoftheverticaldeflectionduringthecompleteexperienceversusthetotalverticalloadappliedtothegeotextile（Q=ownweightoftheclaylayer+overloadq）isplottedonthe（Fig.5）。

Layerofunreinforcedclay

Theinitialobservationmadeonthefrontoftheunreinforcedearthworkrevealedanetworkofcrackssimilartothatobservedinthereinforcedearthwork.Thehorizontalcrackduetointerlayerdetachmentsplittheearthworkintotwosub-layersabout0.3and0.7mthick.

Whileemptyingtheexpandedclaybeadswecouldobservethegradualsubsidenceofblocksofthelowersub-layerby0.3mwhichfinallyafterafirstoverloadingwasdroppinginthecavity.

Theevolutionofthedeflectionversustheload（Q）andtheelapsedtimeisplottedontheFig.7.Duetothedetachmentofthelowersub-layer,onlythedeflectionatthebottomoftheuppersub-layercanbemonitored.It’sworthnotingthat,attheintermediatestageofunloadingonthefigure6,severalcracksinitiateintheuppersub-layer.

Thispreliminaryexperience,althoughsereveandschematic,demonstrates:

-thepoorductilityofclaymaterial,evenifcompactedatawatercontentfarhigherthantheWopt

-theefficiencyofgeosynthetictostopadramaticcollapsingiftheclaybarrier,butnotsufficienttopreventitscrackingevenifthestiffnessoftheselectedgeosyntheticcanbeconsideredinthehighrange.

Behaviorofcapcoverfornuclearwasteoflowactivity

Thesafestorageofnuclearwasteisabigissue.Fornuclearwasteoflowactivity,it’sconsideredasacceptabletoselectasurfacestorage,ontheconditionthattheintegrityofthecapovercouldbeguaranteeduntil300years.Theradioactivematerialispackagedinparcelsofdifferentshapesandgenerallyofaunitvolumehigherthanseveralm³.Thespacebetweentheparcelsisfilledwithsand.It’simportanttomaintainthewasteinadryconditiontoavoidaleachingprocess.

TwolandfillofthistypeareexistinginFrance,LaHaguewhichwasclosedin1991andSoulaineswhichwasopenin2006andtheexperiencerelatedtothecapcoverforthesetwositesisrelatedhere.

LaHaguelandfill17yearsold

Thespecificshapeofthecoverwasselectedinordertoobtainanefficientcollectionofrun-offwater.Thecompletecansystemconsist,fromthebottomtothetop,ofacoarseaggregatelayer（0.6mthick）,asandlayer（0.2m）,abituminousgeomembrane,asanddrain（0.3m）,abiologicalbarrierofcoarseaggregate（1m）andatopsoil（0.2m）（Fig.8）.Thegeomembranehasamassperunitarea（6㎏/㎡）,atensilestrengthof20kN/mforanelongation（40%）.Theseamsaremadeonsitebyweldingwithanoverlapof0.20m.

After17years,globalbehaviorofthebarrieriscorrectexceptmainlyinonepartwhereadifferentialsettlementwasobserved.

Soulainesnewlandfill:

Thestructureofthecapbarrierisfollowingthespecificregulationforhazardouswastewhichincludesaclaylayerof1meterthickaboveageomembrane（Fig.9）

Wasteisstoredinblocksofvariableshape,intheformonbigbags,tanksandbarrelsandspacesbetweenblocksarefilledwithsand.Duetothistypeofstorageandprevalenceofvoidswhich,settlementswithinwastearelikelytooccurasinthepreviouscase.Thecharacteristicsoftheclayarepresentedinthetable1:

FieldtestprocedurefortheSoulainesexperience

Theinfluenceofdifferentialsettlementswithinthewastemassonthecapcovercanbemodelledbysubmittingaclaylayertobendingstress（JessbergerandStone,1991;ViswanadhamandSengupta,2005）.Intheframeworkofthepresentpaperonlyburstingtes