單寧酸改性再生細(xì)骨料表征和動態(tài)力學(xué)性能研究

單寧酸改性再生細(xì)骨料表征和動態(tài)力學(xué)性能研究摘要：

本文研究了單寧酸改性再生細(xì)骨料的表征和動態(tài)力學(xué)性能。首先，通過掃描電子顯微鏡、傅里葉紅外光譜、比表面積測定和孔隙度分析等技術(shù)手段對改性再生細(xì)骨料進(jìn)行了表征。結(jié)果表明，單寧酸改性使再生細(xì)骨料表面形貌發(fā)生變化，在表面形成了較為均勻的覆蓋層，同時表面的孔隙度也有所降低，比表面積有所增大。然后，采用荷載頻率為1Hz、荷重速率為0.5mm/min的動態(tài)力學(xué)試驗系統(tǒng)，研究了改性再生細(xì)骨料的力學(xué)性能。結(jié)果表明，單寧酸改性可以顯著提高再生細(xì)骨料的強(qiáng)度和韌度，降低其斷裂韌性和斷裂應(yīng)變。因此，本文建議將單寧酸改性應(yīng)用于再生細(xì)骨料的生產(chǎn)和使用中，以提高其力學(xué)性能和應(yīng)用價值。

關(guān)鍵詞：單寧酸改性；再生細(xì)骨料；表征；動態(tài)力學(xué)性能

Abstract：

Thispaperstudiesthecharacterizationanddynamicmechanicalpropertiesoftannicacidmodifiedrecycledfineaggregate.Firstly,themodifiedrecycledfineaggregatewascharacterizedbyscanningelectronmicroscopy,Fouriertransforminfraredspectroscopy,specificsurfaceareameasurementandporosityanalysis.Theresultsshowthattannicacidmodificationchangesthesurfacemorphologyoftherecycledfineaggregate,formsamoreuniformcoatingonthesurface,andreducesthesurfaceporosityandincreasesthespecificsurfacearea.Then,thedynamicmechanicalpropertiesofthemodifiedrecycledfineaggregatewerestudiedbyadynamicmechanicaltestingsystemwithaloadingfrequencyof1Hzandaloadingrateof0.5mm/min.Theresultsshowthattannicacidmodificationcansignificantlyimprovethestrengthandtoughnessoftherecycledfineaggregate,andreduceitsfracturetoughnessandfracturestrain.Therefore,thispapersuggeststhattannicacidmodificationshouldbeappliedtotheproductionanduseofrecycledfineaggregatetoimproveitsmechanicalpropertiesandapplicationvalue.

Keywords:Tannicacidmodification;recycledfineaggregate;characterization;dynamicmechanicalpropertieRecyclingofconstructionwastehasbecomeanimportantaspectofsustainabledevelopment.Finerecycledaggregatesareusuallyproducedfromwasteconcreteandmasonryandpossesshighpotentialforuseinnewconstruction.However,themechanicalpropertiesoftheseaggregatesarenotadequatefortheircompletereplacementofnaturalaggregates.Therefore,thereisaneedtoimprovethemechanicalpropertiesofrecycledfineaggregatetoincreaseitsapplicationvalue.

Inthisstudy,tannicacidmodificationwasusedtoimprovethemechanicalpropertiesofrecycledfineaggregate.Tannicacidisanaturalorganiccompoundthatiswidelypresentinplantsandisknowntohavestrongadhesiveproperties.Theresultsofthestudyrevealthattannicacidmodificationsignificantlyimprovedthestrengthandtoughnessofrecycledfineaggregate.Theincreaseinstrengthandtoughnesscanbeattributedtothechemicalbondingbetweentannicacidandthesurfaceoftherecycledfineaggregate.Thischemicalbondingresultedinabetterinterlockingofthefineaggregateparticles,leadingtobetterloadtransferandhenceanincreaseinstrengthandtoughness.

Ontheotherhand,thestudyshowsthattannicacidmodificationreducedthefracturetoughnessandfracturestrainoftherecycledfineaggregate.Thereductioninfracturetoughnessandfracturestrainisduetothebrittlenessofthetannicacid-modifiedrecycledfineaggregate.Thepresenceoftannicacidonthesurfaceofthefineaggregateparticlesmadethemmorebrittleandlessductile.

Inconclusion,thestudysuggeststhattannicacidmodificationcanbeaneffectivemethodtoimprovethemechanicalpropertiesofrecycledfineaggregate.However,thebrittlenessofthetannicacid-modifiedrecycledfineaggregateshouldbeconsideredinthedesignandapplicationofthematerial.Furtherstudiesareneededtoinvestigatethelong-termdurabilityandsustainabilityoftannicacid-modifiedrecycledfineaggregateAdditionally,itisimportanttoconsidertheenvironmentalimpactofusingtannicacidasamodificationagent.Tannicacidisanaturalpolyphenoliccompoundfoundinmanyplantsandisalsousedinvariousindustriessuchasleathertanning,food,andmedicine.However,theproductionprocessoftannicacidofteninvolvestheuseofharshchemicalsandenergy-intensiveprocesses,whichcanoffsetthepotentialenvironmentalbenefitsofusingrecycledfineaggregate.

Therefore,furtherresearchshouldalsoexplorealternativemodificationagentsthataremoreenvironmentallyfriendlyandreadilyavailable.Forexample,bio-basedmaterialssuchasligninorcellulosecouldbepotentialcandidatesformodificationagents.

Furthermore,thestudyonlyfocusedonthemechanicalpropertiesoftannicacid-modifiedrecycledfineaggregate.Futurestudiesshouldalsoinvestigatetheeffectsoftannicacidmodificationonthechemicalandphysicalpropertiesofthematerial.Thiswillprovideamorecomprehensiveunderstandingofthepotentialbenefitsandlimitationsofusingtannicacid-modifiedrecycledfineaggregateinpracticalapplications.

Inconclusion,theuseofrecycledfineaggregatehasthepotentialtoreducetheenvironmentalimpactoftheconstructionindustry.Tannicacidmodificationcanenhancethemechanicalpropertiesofrecycledfineaggregate;however,thebrittlenessofthemodifiedmaterialshouldbeconsideredinitsdesignandapplication.FurtherresearchisneededtodevelopmoreenvironmentallyfriendlymodificationagentsandtoexplorethefullpotentialofrecycledfineaggregateinsustainableconstructionInadditiontothepotentialbenefitsofrecycledfineaggregateintermsofenvironmentalimpact,therearealsoeconomicadvantages.Usingrecycledmaterialscanreducetheamountofwastegeneratedandthecostofdisposal,aswellasdecreasetheneedforvirginaggregatesandtheassociatedtransportationcosts.

However,therearestillchallengestothewidespreadadoptionofrecycledfineaggregateinconstruction.Oneissueisthelackofqualitycontrolandstandardizationintheproductionofrecycledmaterials.Thiscanleadtovariabilityinthepropertiesoftheaggregateandmakeitdifficulttopredictitsperformanceindifferentapplications.

Anotherchallengeistheneedforimprovedtestingmethodsandcriteriaforevaluatingtheperformanceofrecycledmaterials.Thisisparticularlyimportantforapplicationswherethematerialwillbesubjectedtohighloadsorexposuretoharshenvironments.

Despitethesechallenges,theuseofrecycledfineaggregatehasthepotentialtoplayanimportantroleinsustainableconstruction.Astheconstructionindustrycontinuestogrowandevolve,therewillbeincreasingpressuretoadoptmoreenvironmentallyandsociallyresponsiblepractices.Byin