玻璃纤维增强水泥制品(GRC)及工艺 大连大臣GRC水泥制品

玻璃纤维增强水泥制品(GRC)及工艺大连大臣GRC水泥制品URL:Contactinformation:dcgrc2004@163.comGlassfiberreinforcedcementproducts(GRC)andprocessGlassfiberreinforcedcement(Glass,fiber,Reinforced,Cement,abbreviatedasGRC)isacompositematerialmadeofglassfiberasreinforcingmaterialandcementpasteorcementmortarasmatrix.Fromtheperspectiveofthedevelopmentofbuildingmaterialsindustry,largebuildingmaterialsmustbegreenmaterialsforsustainabledevelopment.Cementandcementbasedmaterialsarethelargestman-madematerialsnowadays.Worldcementproductionhasmorethan1billion500millionT(ourcurrentcementproductionhasreachedtheworldcementoutput1/3),basedonprojections,thetotalcementitiousmaterialsin60-70billionT.Themainresourceconsumedisestimatedtobe1billion500millionTofhigh-qualitylimestone.Sandstoneaggregate4billionm3,emissionsofCO₂(majorgreenhousegases)morethan12t,thereareotherharmfulgasesandalargenumberofdust,seriouslypollutingtheenvironment.Today,China'sannualoutputofcementremainsat500millionT,accordingtoareasonableindextoestimatetheannualenergyconsumption.Resourcesandtheenvironmentcausedbytheburdenasshownintable5-4.Therefore,regardlessofourcountry,ortherestoftheworld,wemustrelyonscienceandtechnology,manpower,energyconservation,environmentalprotection,orcementandcementbasedmaterialswillbecomeunsustainablematerials.Cement-basedmaterialsmustbedevelopedtohighperformance,toreducedosage,prolonglife,enhancefunctionality,andespeciallyreduceenvironmentalcosts.SincethePortlandcementcameintobeingin1824,ithasexperiencedmanygreatdevelopments,withthemainpurposeofexpandingtheuseandimprovingthemechanicalproperties:Portlandcement,mortar,concrete,reinforcedconcretegate(1850),(1900),asbestoscementdoorofprestressedconcrete,concreteadmixtures(1929)(1935)(1950s),polymercementconcrete,highstrengthconcrete(1970s),highperformanceconcrete(1990s).FiberreinforcedselfasbestoscementtocementbasedmaterialsGRC1950s(glassfibercement)andsteelfibercementin60s(SFRC),carbonfiberreinforcedcement(CFRC)in80s,andeventhenthefiberreinforcedpolymercement,mechanicalperformanceisgreatlyimprovedandexpandeduse.Fromthehistoricalpointofviewofmaterialdevelopment,themud,gravelandgrasspastewereoriginallyused.Limedust.Allkindsofconcrete,andcementbasedcompositematerialsinmoderntimes,showsthatthecompositematerialisoneofthemainwaysofdevelopment.Glassfiberreinforcedcement-basedmaterialsarenewachievementsincompounding,whichhavebeendevelopingrapidlysinceWorldWarii.Theideaofcompositesuperimposedeffect,hasimportantsignificanceforthehighperformancematerialsavailable,"saidthe3Formula1+2.Forexample,inhigh-performanceconcrete(HPC),itusesavarietyofcomposite,notonlycompositecementingmaterial,butalsocompositefineadmixture,compositeadmixture.Glassfiberreinforcementplaysanimportantroleinthecompositeprocess.Itplaysakeyroleinincreasingtoughnessandimpactresistanceintheabovespecialhighstrengthcement-basedmaterials.Inaddition,thereareavarietyofcement,glassfiber,polymercomposite,suchasglassfiberreinforcedpolymermodifiedcement.Thepolymerincreasesthebondstrengthbetweentheglassfiberandthecementstoneinthecementhardenedbody,sothatthereinforcingeffectoftheglassfiberisfullyrealized,Therebyincreasingelongationandtoughness(falsetoughness).Therefore,bendingresistanceandtensileresistance.Theimpactresistanceisgreatlyimproved,showingobviousperformanceoversuperpositioneffect.Sincetheproblemofcarcinogenesisofasbestoshasbeenputforward,asbestoscementwithexcellentpropertieshasbeengreatlyaffected,butthetechnologyandequipmentofasbestoscementisthemostadvancedintheconcreteandcementproductsindustry.Onthisbasis,explorenewideas,innovationefforts,willallkindsofglassfiberandthequalityofcementbasedmaterials(suchasHPC,UHPCetc.)together,anewcompound,thecementbasedmaterialsshortcomingswereimproved,whichgreatlyimprovestheperformanceandcreatenewgreenbuildingmaterials,expandingtheuse,forthebenefitofmankind.Cementbasedbuildingmaterialshaveaprominentfeature,thatis,highcompressivestrengthandflexural(flexural)strength.Tensilestrengthandimpactstrengtharelow.Itisaneffectivemethodtoimprovetheperformanceofcement-basedmaterialsbymeansoffibermaterials.Improvethebendingresistanceofcement-basedfiber(%)onlysomestrengthandtensilestrength,butcannotimproveitsantiimpactproperties;somefibercanonlyimprovetheimpactresistanceofthecementmatrix,butcannotimprovetheflexuralstrengthandtensilestrength;andtheglassfibercannotonlyimprovethebendingofcementbase.Tensilestrengthcanalsoimproveitsimpactstrength.Thetensilestrengthofglassfiber(hightensilestrengthupto17702550MPa)elasticmodulusandhigher(about70GPa,2.5timesforthecementmatrix)cangreatlyimprovethestrengthandtoughnessofcementmatrixtoprovidethenecessaryguarantees.30yearsathomeandabroadtostudytheperformanceofglassfiberreinforcedcement,glassfiberinthecementmatrixcanbegreatlyimprovedwith4%-5%ofitsmechanicalproperties.Thegeneraltensilestrengthofcementmortaris2-3MPa,100-150limitelongationdeformationUE,flexuralstrengthis5(%)-7MPa,theimpactstrengthisabout2kJ/squaremeters,with4%to5%whentheglassfiber,thetensilestrengthreached912MPa,limitextensiondeformation8000to12000Muepsilon,theflexuralstrengthreached20(%)-25MPa,theimpactstrengthreached1520kJ/squaremeters.Youcanaddasmallamountofglassfibercementmatrixtogetsuchgoodresults,ofcourse,isanencouragingthing,asakindofmaterial,inparticularforthemanufactureofbuildingmaterials,peoplearemoreconcernedabouttheproblemofitsdurability,hopebuildingmaterialshavealonglifeandgoodsafetyreliability.Forthisnewtypeofglassfiberreinforcedcementcompositematerials,glassfibercanmaintainitshighinthecementmatrixstrengthandtoughnessisthekeytoensurethetougheningeffectofglassfiberreinforced.Inpractice,theerosionandembrittlementofglassfiberincementmatrixhavebeenfound,andthemechanismofcorrosionandembrittlementhasbeeninvestigated,andtheglassfiberhasbeenimprovedbyvariousmethods.Ontheonehand,improvetheantierosionabilityofalkaliglassfiber,mainlyfromtwoaspects,namely,orchangethechemicalcompositionofglassfiber,orthesurfaceoftheglassfiberbyalkalitreatment;ontheotherhandisthematrixmaterialwasmodified,orgrayvolcanoinPortlandcementmaterialisaddedto.Toimprovethestrengthandtoughnessofthematrix,Orisaddedinthematrixpolymermatrix,topreventfromphysicalandchemicalerosion,orissuitableforthedevelopmentofglassfiberusingenvironmentoflowalkalinitycement,toreducethecementhydrationproductsCa(OH)₂content.ThetechnicalrouteadoptedbyJapanandtheUnitedKingdomisthecombinationofalkaliresistantfiberglassandmodifiedPortlandcement.Chinabuildingmaterialsinstituteadoptsthedoubleinsurancetechnologylineofalkaliresistingglassfiberandlowalkalinitycement.Thelong-termdurabilityofglassfiberreinforcedcementiswellsolved.Throughacceleratedagingtests,itisassumedthatthesafeservicelifeofGRCisatleast50years.Thedurabilityofglassfiberreinforcedcementhaslaidasolidfoundationforthewideapplicationofthiskindofcement.StartingfromtheuseofalkaliresistantfiberglasstomanufactureGRCproductsandtobeginproductionatanindustrialscale,theinternationalGRCproductindustryhasexperienced30yearssofar.Atpresent,theworldhastencountriesandregionsindifferentscaleproductionanduseofGRCproducts,GRCproducts,globalannualproductionisestimatedat450thousandtons,thehighestyieldwhenpushJapan,theannualoutputofabout120thousandtons,theannualsalesofGRCproductshasreachedmorethan$100million,theannualoutputofGRCproductsinEuropeestimateoflessthan100thousandtons,whichaccountedforabouthalfofgermany.InAsia,thescaleofChina'sGRCindustryhasbeenexpanding,theannualoutputhasreached4-5tons,Singapore,Malaysiaandothercountries,aswellasChina'sTaiwan,HongkongandotherregionshavealsoproducedGRCproductsformanyyears.CharacteristicsofglassfiberreinforcedcementproductsThemainpropertyofcementisitscost,adaptabilityandhighcompressivestrength.Themaindisadvantagesarelowtensilestrengthandbrittleness.Therefore,asmentionedabove,addingglassfibercanimprovetheabove-mentionedshortcomingsofcement-basedmaterials.Theadvantageofglassfiberreinforcedcementisthatitsproductsaremuchstrongerthansteelbars,cementthin(typically10cmormore),andhavelightercomponentcapabilities.Andreinforcedconcretemusthave25mmormoreprotectivelayer.Glassfiberreinforcedcementissimilartoordinaryreinforcedconcreteinmanyways,suchasweatherresistance,nonburning,easymaintenance,lowheatflowandcorrosionresistance.Andtherearesomeadvantagesthanconcrete,suchashighstrengthtoweightratio,itcanbeusedforthinsection;earlywithhighimpactresistance;easytoshape;easytoformsemiinsulationstructureofhighstrengthcomponentsandothermaterials;canusesimpletoolsandawiderangeofothercutting;smoothsurfaceforuse.Themaindrawbackisthatithasnotbeenallowedtobeusedinload-bearingstructures.Itcanbeusedforsemistructuraloccasions,suchasvariouspartitions(curtainwall),cancompetewithmetalandplasticwallwall.(1)physicalpropertiesThedensityofGRCmaterialisnotaffectedbyage.Apieceof1squaremeters,6cmthickflatplateweighsabout12kg,GRCinnormalweightprecastconcreteslab20%.Shrinkageandwatermovementwithallthesamecementbasematerial,thevolumechangeofGRCisdividedintotwoways:preliminaryhardeningofirreversibleshrinkage,asafunctionofC/W,andlong-termwatertransfer,whichiscausedbythechangeofnormaltemperature.GlassfiberreinforcedshrinkagehadnoinfluenceontheGRC,buttheadditionofsilicamatrix,asasupplementtoreducethehardnessofthetwokindsofcontraction.Thesand/cementisbigger,Thesmallertheshrinkage,themore25%sandinthematrix,thetheoreticallimitmaybe1.5cm/m.PracticalGRCcurtain,intheweatherofEngland,watermovementisonlyhalfofthislimit,butthisvalueisslightlymorethanordinaryconcretewatermovement2times.Ifthetablethasaprotectivefilm,itshrinksbecauseitlimitsthemovementofmoisturewithinthesurfaceoftheGRC.PermeabilityandcondensationofGRCcanpreventwaterpenetration,buthavelowervaporpermeability.Asaresult,steampartitionsarenotrequiredfornormaluse.However,insomespecialcases,suchascoldplate,shouldconsiderpossibleinterlayercondensationandplaceastopinthebuildingmaterialwithsteam.Thehumidityandheatflowarethesameasthoseofothercement-basedmaterials.ThethermalexpansionofGRCisverylow.Whenthetemperaturedifferenceis70degrees,Mislessthanlmm.InBritain,thermalandthermalconditionsvarygreatly,andthermalexpansionandcontractioncanbeoffsetagainsteachother,thusreducingtheoverallsizeofthechange.IntheMiddleEast,thehotanddryclimatehaslittleimpactonthelong-termperformanceoftheGRC,comparedwiththetemperateclimate,whichisresistanttocomplexcyclesofsubzerotemperaturesandfreezingandthawingconditions.ChemicalresistanceofGRCtochemicalcorrosionresistanceisthesameasthatofconcrete,buttheporosityislowerthanthatofmostconcreteormortar,soGRChasbetterchemicalresistance.Butthecorrosionresistanceofacidsandsulfatesispoor.SpecialcementshouldbeusedinsteadofordinaryportlandcementasthematrixmaterialofGRC.FireretardantGRCdoesnotburnatallandfiresinsidebuildings.Goodflammabilityandflameretardantpropertiesareclassifiedasanonflammableflame.(two)longtermperformanceWithmanymaterials,especiallythecontentofreinforcingmaterialofdifferentmaterials,changethemechanicalpropertiesofGRCwithsomecontrolfactorandchange,suchas:(1)thelengthofglassfiber,contentandorientation;(2)theratioofmatrixmaterial/cement/waterandair;(3)theprocessofsprayproductsclothorpremixingmethod;(4)thehardeningtimeandhardeningcondition;(5)age;(6)theconditionsofuse.Thecombinationoftheabovesixcandeterminetherangeofperformancecriteriaforamaterial.Butmixing,manufacturingmethods,andhardeningarefunctionsofcomponentdesignandspecification,andagealsohasafundamentalimpactontheperformanceofGRC.Cementproductdevelopment19681969yearsofalkaliresistantglassfiberreinforced,alargenumberoflong-termperformancetestisusedtoverifyGRC.Themainconclusionfromthe5yearexperimentalplanisthatthetensilepropertiesofthematerialarereducedandsomeembrittlement,especiallyinexposedmoistortemperateweather,ismostsevereinGRC.Inhightemperatureandhighhumidityplaces,suchasthetropics,embrittlementisverypronounced.(three)mechanicalpropertiesLearnhowtoGRCinthedeformationunderload,stress/strainbetweenisveryimportant,becauseofthedifferenteffectsofalkaliresistantglassfiberincement-basedmaterialswithglassfiberreinforcedplasticcompositematerialsinthemechanism.Becauseofthehighhardnessoftheglassfiberthantheplasticmatrix,theglassfiberreinforcementbearsmostoftheloadwhenaloadactsonthecomposite.ForGRC,theglassfiberisonlystifferthanthecementmatrixatthemargin,WhenaloadontheGRCcomplexwillproducethreedifferentphenomena:(1)thecementmatrixtogetherwithglassfiber,althoughsomecementunderload;(2)thecementmatrixshowedsmallcracking,suddenloadtransfercausedbytheglassfiber,andthematrixaccordingtothefiber,inordertoobtaincontinuousload;(3)loadconsistsentirelyofglassfiberundermicrocrackingandfailuretype.Fiberelongationwithoutbreakingawayfromthecementmatrix,whichgivesconsiderableductilitytotheGRC.BecausethepropertiesofglassfiberreinforcedmaterialwithintheGRCandthetraditionalreinforcedconcreteissimilartothatintheloadtransfertothefiberreinforcedconcrete,similartotheloadtransferredtothereinforcedcementmatrixhavethesametypeofmicrocrack.Two.HighdurabilityglassfiberreinforcedcementcompositeSinceearly1970s,manycountriestothedevelopmentofglassfiberreinforcedcement(GRC)products,thedevelopmentofGRCinwesterncountriesismainlybasedontheuseofleadalkaliresistantglassfiber(ARGF)asareinforcingmaterial,withPortlandcementasthebase,butthetestresultsshowthatAGRF-OPCandGRCaremainlymadeofthefollowingtwoquestions:(1)exposedtotheatmosphereorinahumidenvironmentwithultimatetensilestrength.Theultimateflexuralstrength,impactstrengthandtoughnessdecreasegreatlywithtime,especiallythedecreaseoftoughness.(2)theGRCouterwallpanelwhichismountedonthemetalframeiswarped,deformedandcracked,andtheceramicplateisstuckontheceramicplate.Westerncountriesforthelong-termdurabilityofresolvingtheproblemofGRC,toexploresometechnicalmeasures,suchasalkaliresistantglassfibersurfacecoatedwithaprotectivelayer,activeingredientadjustmentofalkaliresistantglassfiber,volcanoashactivitymaterialwithcement.Addacrylicpolymeremulsionandsoon,butlittleeffect.Forthisreason,in1980s,theGRCindustryinwesterncountrieswasatalowlevel.Inthemiddleof1970s,ourcountrydevelopedanddevelopedanewgenerationofGRC,adoptingthedoubleinsurancetechnologyrouteofARGFandlowalkalinitysulphoaluminatecement.Acceleratedageingtestat50DEGCsteam.TheacceleratedagingtestandtheBeijingareaatmosphericexposuretestshowedthat20Clong-termwaterimmersiontest,hotwaterof80DEGC,thelowalkalinitysulphoaluminatecementandalkaliresistantglassfibercomposite(LASC+ARGF)madeofGRCintheaboveundervariousexperimentalconditionsofflexuralloadorultimateflexuralstrengthretentionratewassignificantlyhigherthanthatofOPCARGF+GRC,thelowalkalinitysulphoaluminatecementandalkaliglassfiber(LASC+AGF)GRC,Portlandcementandalkaliglassfiber(OPC+AGF)GRC.ComparedwiththebendingtoughnessofGRCinthesamesetof180hintheatmospherefor28days,thereisnoobviousdecreaseintheflexuraltoughnessofLASC4ARGFproducedbytheacceleratedagingofGRCat50DEGC.LASC+ARGFGRCmadetheshrinkagerateoflessthanOPC+productsmadeofARGF.Therefore,itLASCARGFdurabilitymadeofGRChigh.Atpresent,thiscombinationofGRCisnotonlyusedtomakecorrugatedtile,bathtub,biogaspool,alsousedtomakesomeminorcomponentsorproducts,suchasgrain,waterpressure.Trussroofpanelandshedsupportetc..Themiddleofthe1980sJapanCentralglasscompany,Chichibucementcompany,NecCorpjointlymadethedevelopmentofhighaluminiumcontentofARGFwithlowalkalinitycementanewgenerationofGRC,comparedwithOPC+ARGFmadeofGRC,itsdurabilityisimprovedobviously.ThereisacommonopiniononthefollowingARGFinOPCmatrixbyerosionmechanism:(1)highalkalinitywatersolutionofOPCmatrixwithchemicalerosionontheARGF(2):Ca(OH)₂crystaldeposition,ARGFprecursorinthecracksinthegrowthoftheoriginalsilkloseflexibleandbrittle.Secondly,itisconsideredthatthehydrationofcementmatrixisthekeytothedurabilityofGRC.Forthisreason,lowalkalinitycementorcementforsilicatesystemshouldbemodifiedtosubstantiallyreduceitsalkalinity.Evenwithsomesalt(CaCL₂,AgCl₂,CdCl₂,etc.)watersolutiontreatmentofglassfibersurfacecanalsoplayaprotectiverole.Ithasbeensuggestedtoadd2%sand-10%calciumchlorideglassreinforcementcorrosioncausedbyalkaliincement,calciumchlorideinaqueousmediumwithPortlandcement,andthereactionofhydrogenchloridecalciumaluminate,calciumsilicatehydratewillbedepositedonthesurfaceofthefiber,thuspreventingcorrosion(Japanesepatent1321711).Nowthemethodoftreatingglassfibersurfacecannotonlystabilizethestrengthofglassfiber,butalsoincreasethestrengthofglassfibertoacertainextent.Onemethodislow-temperatureionexchange,whichreliesonK⁺ionsinKNO₃saltmeltsinsteadofNa⁺inglassTheformationofcompressionsurfacelayerion,theoptimumprocessingsystemofglassfiberinKNO₃meltintheshort-term(<5min)zone,dependingonthecompositionofglassfiber,glasstransitiontemperatureandtheplasticstatetohardbrittlestate.Undersuchtreatmentconditions,thestrengthofthecementstabilizedglassfibercanbeincreasedby40%.Canalsousethenewmixedwithmethacryloylderivativesofepoxyandepoxyflavorinthefeedingfeedinggapbased.Toavoidalkalicorrosiononthesurfaceofglassfiber.Aseriesofphysicalandchemicalresearchshowsthatepoxymodifiednewhydratefeedingtogorgeboundarylayer,andgreatlyreducetheamountofcalciumhydroxide,lowalkalisilicatehydratecontentincreased.Thiscanweakenthediffusionofbasicionstothesurfaceofglassreinforcement.Epoxymethacrylicpolymeracidicflavorfeeding,withlastingelasticity.Theadsorptionofhydratedsilicateonthesurfaceofthefibercantransformthealkalineenvironmentintoacidandforminsoluble,loosestructurecompounds.Inalkalineconditions,therateofpolymerizationoftheprotectivelayerdependsonitscomposition,aswellasonthechemicalactionofthecementmatrix,glassandsurfaceactivegroup.Whenusingthiskindofpolymertocementthealkalineoxideglassframemediummigrationwillreduce2-3ordersofmagnitude,soinordertoimprovethestrengthperformance,prolongthedurabilityofprotectivelayerthicknessshouldbe100-150muepsilon.Thepresenceofthepolymerprotectivelayerformsabarrierforthediffusionoffilm,allowingCaZtopassatnolessthan10,mZ,andfirespeed,Ensurethechemicalstabilityofglassreinforcement.Thepolymerinterfacelayerisfilledwithairholesandreinforcestheadhesionbetweentheglassreinforcementandthesubstrate.Forglassfiber,itcanreducetheerosionofcementmatrixundertheconditionofreducingthealkalinityofcement.AddingflyashIncement,itcanreducetheconcentrationof"OH"and"ion"inhardenedcementliquidphase.Practicehaspointedoutthattheglassfiberisrelativelystableinhardenedaluminacement.ThesolidificationhardeningprocessofhydratedbauxitecementseemstoberelativeSimilartoPortlandcement,itisactuallydifferentfromthehydrolysisproductsofPortlandcement,ifthehydratedcomponentofPortlandcementisoxidizedbyhydrogenCalciumandhydratedcalciumaluminateareformed,andaluminacementhydratestoformaluminiumhydroxideandhydratedcalciumaluminate,whichcrystallizeAnditcanreducerecrystallizationprocess.WhenthePortlandcementishardened,theliquidpHis