土木中外文翻译

土木中外文翻译_文档视界OnTheApplicationofHigh-PerformaneeConcrete

SummaryThehigh-performaneeconcreteisamaindirectionofthetechnicaldevelopmentofrecent

concrete,theforeignscholarhascalledthattheconcretein21stcentury.Norwaycarriedonresearchtothisatfirstin1986,namedformallyfromAmericanNationalStandard,technologicalresearchinstitute(NIST)

andaseminarhostedtogetherofAmericanConcreteInstitute(ACI)in1990.Conferencestipulatehigh-performaneeconcretetohavewhomsomeperformaneerequirehomogenizetheconcrete,mustadoptthe

strictconstructioncraft,adopthigh-qualitymaterialformulate,easytowatersmash,emanate,mechanicsperformaneesteady,earlyintensityhigh,withperformaneesuchastoughnessandvolumestabilitydurableconcrete,especiallysuitablefortheskyscraper,bridgeandopentothebuildingstructureoftheharshenvironment.

Keywordsconcrete;performance;engineering;application

1.Introduction

Recenthigh-performaneeconcreteisthemaindirectionofthedevelopmentofconcretetechnology,foreignscholarshavecalledthe21steenturyconcrete.Norwayin1986,thiswasthefirststudyin1990bytheNationalInstituteofStandardsandTechnology(NIST)andtheAmericanConcreteInstitute(ACI)ataseminarco-hostedaformalnaming.TheGeneralAssemblyforhigh-performaneeconcreteisacertainperformaneerequirementsoftheuniformqualityofconcrete,itmustadoptastrictconstructiontechnology,usinghigh-qualitymaterials,preparation,easeofpouringpound,non-segregation,mechanicalpropertiesandstability,highearlystrengthwithtoughnessandsizestabilitydurabilityperformaneeofconcrete,especiallyforhigh-risebuildings,bridges,andexposuretoharshenvironmentsinarchitecturalstructures.Asanintegratedhigh-performaneeconcretewithexcellenttechnicalcharacteristicsofmaterialsathomeandabroadhasarousedworldwideattentionwiththeengineeringandconcern.10years,theworld,manycountrieshaveinvestedagreatdealofmanpower,financialandmaterialresourcestoconducttheresearchanddevelopmentapplications,toenablehigh-performanceconcretetechnologyhasmadegreatprogressintheselectionofrawmaterials,mixdesign,physicalandmechanicalpropertiesof,durability,workability,structureandperformaneeaswellasapplicationoftechnologyhavemadeboththeoreticalbasisanditspracticalvalueofscientificandtechnologicalachievements.

In1993,thetechnicalcommitteeunderAmericanConcreteInstituteproposedanewhigh-performanceconcretewasdefined:Meetprojectspecialvariousperformanceofrequirement,butincludingeasytowater,smashinsteadofemanating,highIong-termmechanicsperformance,highearlyintensity,highandtoughandtensileandhighvolumestability,ortheservicelifeintheharshenvironmentisforalongtime,andhomogenizinggoodconcrete.Inrecentyears,AmericanConcreteInstituteprovidesmoreconcisedefinitiononapieceofcharactersagain:"Thehigh-performaneeconcreteisthatonekindcanaccordwithspecialperformanceandsynthesizetheconcretewiththehomogeneityrequirement,theconcretecangetwithregularconcretecomponentmaterialandcommonmixing,habitmethodsmashedandmaintainedtowateroften."High-performaneeconcrete,itisusedforsignifyingtheconcretewithhighworkdegree,highstrengthand

highdurabilitybeginning.Thiskindofconcretemustbedesignedandpossessechighvolumestability.

Forreduceconcreteshrinkanddofractureproducedtocontractwithtemperature,mustlimitthegroutcontentintheconcretemixture.Thehigh-performaneeconcreteamountoftotalgroutlimitedofdesignmethodofmatchratiothatMehtaandActcinputforwardis1/3oftheconcretevolume;Allowsomesilicatecementspendvolcanicashorhavegluepersonwhocongealtomix,shutmaterialreplace.AcTcinhasbeenprophesied:Mixslay,flyash,silicaflour,inferiorclay,thericehusksdustandthreeyuanofthelimestonepowderandmixcementbesidescanmakethepreparationofthehigh-performaneeconcretemoreeconomicing,stillcangiveplaytoexceedingapileoffunctionofthem,improveitspropertywhilemixingandhardeningnewly.

2.Highperformaneeconcreteinmodernengineering

Highperformaneeeoncretetechnologyissuccessfullyusedinmanypartsoftheworldofoffshorestructuresandgrewupacrossthebridgeeonstruction,Langley,whodescribedgrowingupacrossafewbridgesinCanadawiththeworkability.Theyareusedinthegirder,mounddepartmentandmoundbase,itis450Kg/m3thatsilicaflourmixcementconsumption,water153L/m3,guideangrypharmaceutical160mL/m3andhigh-efficientwater-reducingagent3L/m3.Itsslumpisprobablyin200mm;Includes6.1%oftoleranee;1d,3d,28dcompressionstrengthare35,52and82MParespectively;Thefoundationandotherbigmixedcementeonsumptionofpiecesofeoncreteare307Kg/m3,flyash133Kg/m3,watereonsumptionisclose,butguidetheangrypharmaceuticalandmixingamountofhigh-efficientwater-reducingagenttoreducebyalargemargin,makeanappointmentin185mminslump;Ineludes7%oftoleranee;1d,3d,28dand90dcompressionstrengthare10,20,50and76MParespectively.AndwaterpermeabilityofU.S.A.andchlorineionfasttopermeatestandardmethodexperimentalresultindicateaccordingtoCanada:Bothpartofeoncretespresentverylowpermeability.Tohigh-performaneeeoncreteeonstructionofstructure,need,putemphasison,strengthenon-the-spotlaboratorytestandinspectionofqualityverymuch.

Anotherareaofdevelopmentofhighperformaneeeoncreteisahighperformaneelightweighteoncrete,

asopposedtosteel,ordinaryeoncretestrength/weightratioisverylow,mixedwithhigh-strengthconcretesuperplasticizerissignificantlyenhancedtheratio;withalargenumberoftinyholeslightweightaggregatetoreplacepartofthenormalaggregate,willbeabletofurtherimprovethisratio.Astheaggregatequalityofdifferentdensityof2000Kg/m3,compressivestrengthat70~80MPahigh-performaneelightweightconcreteinanumberofcountrieshavealreadycommercializedandusedincomponentproduction.InAustralia,Canada,Japan,NorwayandtheUnitedStates,high-performaneelightweightconcretehasbeenusedinfixedandfloatingdrillingplatform;becauseofmudandwater,theinterfacebetweentheaggregatebondstrength,itcanbeimpermeable,sotheerosionoftheenvironmentableisverydurable.

-Dopedsilicapowder10~15%orevenhighersuperplasticizerpreparedmixtureofcementconcrete,

withexcellentadhesion,sothesprayappliedtothewetsprayingthestructuralrepairofconcrete,which

isoneoftheareasofhighperformaneeconcreteapplications.

2.1High-performaneeconcreteinhigh-risebuildingapplications.High-performancecon

crete(>40MPa)overthefirst30-storyhigh-risebuildingsusedforreinforcedconcretestructures,becausesuchbuildingsinthelowerthirdofthecolumns,usingordinaryconcretewhenthegreatcross-section.Inadditiontosavingsinmaterialcosts,ascomparedwiththesteelstructure,speedinguptheadoptionofconcretestructuresisanimportantfeature,sincetheUnitedStatesinChicagoin1965with50MPaconcretepouringLakePointTowersomeofthepillarshasbeeneverywhereinNorthAmericaandothercountriesusinghigh-performaneeconcretetobuildhigh-risebuilding.Chicago79-storyWaterTowerPlacebuildingcolumnsusing60MPaeoncrete;Toronto'sScotiaPlazaBuildingandSeattle'sTwounionSquareBuilding2Buildingsthen90and120MParespectivelyintensityofhigh-performanceconcretepillars.

Applicationexamples:a.high-performanceconcreteapplicationofC80high-strengthandhigh-performanceconcreteinShenyangFangyuanBuilding,OnishiElectricPark,andmanyotherhigh-risebuildingintheapplicationofeoncretefilledsteeltubularcolumns.

b.ShanghaiResearchinthefieldofhighperformanceconcreteinalargenumberofpromisingresultsobtained,ofwhichrepresentativeresultsare:China'stallestbuilding-88C40floorJinmaoToweroncepumpedto382.5m;TomorrowSquareslagpumpingC80eoncrete;inShanghaieducationTVstationbasedoncomplexbuildingmasseoncrete,cementconsumptionaccountedforonly46%ofthetotalcementitiousmaterials,preparationofthefullamountofconcreteslurry,eoncretework,cohesivenessandresistaneetosegregationareveryexcellentperformance,strengthofC40high-performanceconcrete.

2.2High-performaneepavementconcrete

a.High-performaneepavementconcretesignificaneeofthestudy

Withtheincreasingtrafficandtransportrequirementstodevelopthe"long-lifelow-maintenanceroad,"

Withhigh-performaneepavementconcrete,toimprovetheflexuralstrengthanddurabilityofconcreteisthecurrenttrendofdevelopmentofconcretepavement.

b.Overseasdevelopments

Heldin1997attheXVIInternationalConferenceonConcretePavement,pavementdesignproposednot

onlytoraisetheaverageintensityofdemand,butalsomakethedurabilityrequirements.Madeinthedirectionoffuturedevelopmentofultra-hightensilestrengthupto17MPastrengthconcrete,forpavingcontinuousconcretepavement.Improvetheconcretepavementsurfacecompactnessandimpermeabilityareveryimportant,andthisisthroughhigh-performaneeconcretetoachieve.

c.High-performaneepavementeoncretestrength

High-performaneeeoncretepavementimportantfeatureisahighflexuralstrength.Usinghigh-

performancepavementconcretecansignificantlyimprovethebearingcapacityofpavement,extendservicelife,orthinningthethicknessofpavementtoreducetheprojectcost.

d.High-performaneedurabilityofconcretepavement

High-performaneeeoncretepavementmainfeatureisasufficientdurability,resistanttoclimaticandenvironmentaleffectsofIong-termdamagetoensurethatthedesignofpavementandwithintheeoncretecanworkproperly.

e.Highdeformationcharacteristicsofeoncretepavement

(1)Shrinkage

Roadpanelsurfaceareaofgreatevaporation,shrinkagemaybecausedbyTaopanelsurfaceofshrinkagecracks,theneedtoincreaseconservation.

(2)Theflexuralmodulusofelasticity

High-performancepavementconcreteflexuralelasticmodulusE,bymeasurement,onefor4.305104Mpa,2grade4.845104Mpa,3grade4.605104Mpa.Intensityofthreehigh-performaneepavementeoncretemix,theaggregateamountoflesscoarseaggregatemaximumparticlediameterissmaller.

f.Theapplicationof

Applicationofhigh-performancepavementconcreteyieldsignificantbenefits:

(1)increasepavementstrength;

(2)extendthepavementservicelife;

(3)reducingtheprojectcost;

g.Applications

(1)intheU.S.about70%oftheroadpavementusinghigh-performanceconcrete:oneinNorthDakota,1988and1989inthesummer,with20000m3ofconcretepavingthicknessof200mmofthesurface,itswater-cementratioof0.43,cementconsumption100Kg/m3,flyash220Kg/m3;theroadTexasdemonstrationprojecthassuccessfullyadoptedthisnewmaterial.

(2)TheQinghai-Tibetrailwayconstructionprojectfullypromotetheuseof

h.Conclusion

Threeintensitylevelsofhigh-performancepavementconcreteisextremelygoodquality,costofmaterialsbasicallydoesnotincreaseorincreasedmarginally,forthedifferentrequirementsoftheprojectchoosetouse,theconstructionoflow-maintenanceIong-lifepavement,road,itssocial,economicbenefitsareenormous,andworthpromotingandcontinuedresearchtopromotethecountry'sairportscementconcretepavementconstructionandroadpavementengineeringisenteringanewstageofdevelopmenttomeetthegrowingdemandforaviationandtransportationneeds.

2.3MarineConcreteStructures-Durabilityofhydraulicstructurestoenhanceportstudyandproposetechnicalandeconomicrational,easytopromotetheuseofanewmarineengineeringhigh-

performanceconcrete

Spanbridges,underseatunnelsandoffshoreoilplatforms,isaninstanceofthisapplication.

Suchas:a,Shantou,HongKongoutsidetheDeepwaterChannelRegulationProject;bLingdingyangPearlRiverEstuaryDeepwaterChannelRegulationProject;

c,Qingdao,NingboBeilunandotherportsthatcanberth200,000-tonclassbuilttankersandoreshipsdeep-waterberths

2.4FreeVibrationofSelf-compactingConcrete

Duetovibration-freeself-compactingconcretehasaverygoodwork,makingtheconcretefilling,compactness,uniformityhasbeensignificantlyimproved,becominganewconcretetechnology,progressislistedasafamilyofhighperformanceconcrete.

Vibration-freeself-compactingconcreteisthefirststudyfromJapanoverthelastdecadetodevelopandputintoamodernconcreteengineeringtechnology.Sincevibration-freeselfcompactingconcreteinengineeringapplicationscanbemadetoimproveconcretequality,improveconcreteconstructionoperations,tosupporttheconstructionnoiseandimprovelaborproductivity,speeduptheconstructioncostreductionandothertechnicalandeconomiceffect,inrecentyearshavegiventheworldgreatpayattentionto.Japanisexpectedby2003therewillbe1/2workswiththefreevibrationof

concreteself-compactingconcretepouring.

Asthenamesuggests,vibration-freeself-compactingconcreteispouredconcrete,whenself-gravityalonewithoutanyexternalforcetampingtoachieveself-compacting,selflevelingofaconcrete.Vibration-freeSelf-compactingconcreteshouldhavethreecharacteristics:

⑴Mobility;

(2)Goodstability-doesnotdisintegrate;

(3)Reinforcementandtemplatesinanygap,withagoodthroughcapacity,doesnotproduceblocking.

Accordingtotherequirementsofthesethreecharacteristics,vibration-freepreparationofself-compactingconcreteprinciplesandmethodssectionareasfollows:

Freshconcretephaseisaparticlesuspendedsolids,thecontinuousmediumisacementpaste,whichisliquidandConcreteAggregates,comparedwithsolid-phase.Alltheparticlesinsuspension,mobilityandparticlebalancebetweensegregationisnecessary.Freevibrationoffreshself-compactingconcreteintheabsenceofexternalforcetoberealconcreteformworktogivefullfillallthegapsandachievethecompact,moreimportantly,tobothgoodfluidityandstability.

Inordertoobtainhighmobility,wemustfirstreducethefrictionbetweentheparticles.Incorporationofsuperplasticizertoreducethesurfacetensionofparticlesofcourseisnecessary,butvibration-freeperformancerequirementsofself-compactingofview,alonedopedsuperplasticizerwasalsodifficulttoachieve,needstomixedwithacertainamountofultra-finematerial.

Toobtaingoodstability,sothatmaterialsarenotdisintegrate,theliquidmusthavetheappropriaterheology,cannotproducebleedingandpreventparticlesegregation.Toachievethisrequest,alsobemixedwithanappropriateamountofparticlesize40MPa首先用于30层以上高层建筑物的钢筋混凝土结构，因为这种建筑物下部三分之一的柱子，在用普通混凝土时断面很大。除节省材料费用外，

与钢结构相比，加快施工速度也是采用混凝土结构的重要特点，自美国芝加哥在1965

年以50MPa混凝土浇注LakePointTower的一些柱子以来，北美和其他国家到处都在用高性能混凝土建造高层建筑。芝加哥79层的WaterTowerPlace大楼柱子采用了

60MPa?昆凝土；多伦多的ScotiaPlazaBuilding和西雅图的TwounionSquareBuilding两座建筑物则分别有90和120MPW虽度的高性能混凝土柱子。

应用实例：a高性能混凝土应用C80高强与高性能混凝土在沈阳方园大厦、大西

电业园等多项高层建筑钢管混凝土柱中应用。

b上海高性能混凝土研究领域中取得一大批可喜的成果，其中具有代表性的成果有：中华第一高楼一一88层金茂大厦的C4（一次泵送到382.5m；明天广场矿渣微粉C80泵送混凝土；

在上海教育电视台综合楼大体积基础混凝土，水泥用量只占胶凝材料总量的46%配制的混凝土浆量饱满，混凝土工作性、粘聚性和抗离析性能都十分优异，强度达到C40勺高性能混凝土。

2.2高性能道面混凝土

a.高性能道面混凝土研究的意义

随着对交通运输要求的日益提高，发展“长寿命低维护路面”，

采用高性能道面混凝土，提高混凝土的抗折强度与耐久性是当前道面混凝土的发展趋

势。

b.国外发展情况

1997年召开的第十六届国际混凝土路面会议，提出路面设计不仅要提出平均强度要求，还应提出耐久性要求。在未来发展方向中提出抗拉强度达17MPa勺超高强混凝土，

用于铺筑连续的混凝土路面。提高混凝土道面表面的致密性、抗渗性都是很重要的，而

这是需要通过高性能混凝土来实现的。

c.高性能道面混凝土的强度

高性能道面混凝土的重要特征是具有高抗折强度。使用高性能道面混凝土可以显

著提高道面的承载能力，延长使用寿命或减薄道面的厚度以降低工程造价。

d.高性能道面混凝土的耐久性

高性能道面混凝土的主要特征是具有足够的耐久性，能够抵抗气候和环境的长期

破坏作用，保证在道面的设计使用期限内，混凝土能够正常工作。

e.高性能道面混凝土的变形性质

⑴干缩

道面板表面积很大，蒸发量大，干缩有可能引起道面板表面产生收缩裂缝，需加

强养护。

(2)抗折弹性模量

高性能道面混凝土的抗折弹性模量E,经实测，1级为4.305104Mpa,2级为

4.845104Mpa,3级为4.605104Mpa强度3级的高性能道面混凝土的配合比中，骨料用量较少，粗骨料最大粒径较小。

f.应用情况

应用高性能道面混凝土产生显著的效益:

(1)提高道面承载力；

(2)延长道面使用寿命；

(3)降低工程造价；

g.应用实例

(1)在美国大约有70%勺公路采用高性能道面混凝土：其中北达科他州，1988和1989年夏天，用20000m混凝土铺筑厚为200mnH勺路面，其水胶比为0.43，水泥用量

100Kg/m3粉煤灰220Kg/m3;德克萨斯州的路面示范工程也成功地采用了这一新材料。

(1)青藏铁路建设工程中全面推广使用

h.结论

三个强度级别的高性能道面混凝土具有极其优良的品质，材料费用基本不增加或增加不多，可供不同要求的工程选择使用，建造长寿命低维护的道面、路面，其社会、经济效益是巨大的，值得大力推广和不断研究，促进我国机场水泥混凝土道面工程和公路路面工程步入新的发展阶段，以适应日益增长的对航空和交通运输的需要。

2.3海洋混凝土结构一一提