本科毕业土木工程专业英语翻译翻译（1）

译文学院土木建筑工程系专业土木工程学号200501614109姓名李代环指导教师孙敏河南中原工学院控制温度的措施如下

（1）采用改善骨料级配，用干硬性混凝土，掺混合料，加引气剂或塑化剂等措施以减少混凝土中的水泥用量；

（2）拌合混凝土时加水或用水将碎石冷却以降低混凝土的浇筑温度；

（3）热天浇筑混凝土时减少浇筑厚度，利用浇筑层面散热；

（4）在混凝土中埋设水管，通入冷水降温；

（5）规定合理的拆模时间，气温骤降时进行表面保温，以免混凝土表面发生急剧的温度梯度；

（6）施工中K期暴露的混凝土浇筑块表面或薄壁结构，在寒冷季节采取保温措施；改善约束条件的措施是

（1）合理地分缝分块；

（2）避免基础过大起伏；

（3）合理的安排施工工序，避免过大的高差和侧面长期暴露；为保证混凝土工程质量，防止开裂，提高混凝土的耐久性，正确使用外加剂也是减少开裂的措施之一例如使用减水防裂剂，笔者在实践中总结出其主要作用为

（1）混凝土中存在大量毛细孔道，水蒸发后毛细管中产生毛细管张力，使混凝土干缩变形增大毛细孔径可降低毛细管表面张力，但会使混凝土强度降低这个表面张力理论早在六十年代就己被国际上所确认

（2）水灰比是影响混凝土收缩的重要因素，使用减水防裂剂可使混凝土用水量减少25%o

（3）水泥用量也是混凝土收缩率的重要因素，掺加减水防裂剂的混凝土在保持混凝土强度的条件下可减少15%的水泥用量，其体积用增加骨料用量来补充

（4）减水防裂剂可以改善水泥浆的稠度，减少混凝土泌水，减少沉缩变形

（5）提高水泥浆与骨料的粘结力，提高的混凝土抗裂性能

（6）混凝土在收缩时受到约束产生拉应力，当拉应力大于混凝土抗拉强度时裂缝就会产生减水防裂剂可有效的提高的混凝土抗拉强度，大幅提高混凝土的抗裂性能

（7）掺加外加剂可使混凝土密实性好，可有效地提高混凝土的抗碳化性，减少碳化收缩

（8）掺减水防裂剂后混凝土缓凝时间适当，在有效防止水泥迅速水化放热基础上，避免因水泥长期不凝而带来的塑性收缩增加

（9）掺外加剂混凝土和易性好，表面易抹平，形成微膜，减少水分蒸发，减少干燥收缩.许多外加剂都有缓凝、增加和易性、改善塑性的功能，我们在工程实践中应多进行这方面的实验对比和研究，比单纯的靠改善外部条件，可能会更加简捷、经济

4、混凝土的早期养护实践证明，混凝土常见的裂缝，大多数是不同深度的表面裂缝，其主要原因是温度梯度造成寒冷地区的温度骤降也容易形成裂缝因此说混凝土的保温对防止表面早期裂缝尤其重要从温度应力观点出发，保温应达到下述要求1）防止混凝土内外温度差及混凝土表面梯度，防止表面裂缝2）防止混凝土超冷，应该尽量设法使混凝土的施工期最低温度不低于混凝土使用期的稳定温度3）防止老混凝土过冷，以减少新老混凝土间的约束

2.防水混凝土施工质量控制结合经验，对模板的设计、制作安装、钢筋绑扎、混凝土浇筑及养护等关键工序的操作要点进行了阐述，并介绍了成型后混凝土的质量控制标准，以降低工程造价，具有很好的经济和社会效益施工方法

2.1模板制作与安装由于防水混凝土特别强调密实性，所以对模板的制作和安装也相应提高了要求，即要求密实不漏浆，坚固不变形，吸水性要小，宜优先选用竹胶板模板或钢模板严格控制模板间的缝隙大小，超过2mm的必须用海绵条塞缝，对于板面多孔的模板一律不用，同时做好墙柱烂根防治工作，采取根部贴海绵条,底部抹水泥砂浆，浇筑混凝土前，先注入同标号的水泥砂浆由于防水混凝土结构壁厚大多较薄，为保证构件的几何尺寸，常采用内外螺栓拉接的措施，需要注意的是，应在拉接螺栓中间设置止水铁板，以防止水沿着螺栓渗漏，形成引水通路

2.2钢筋制作与绑扎防水混凝土结构对钢筋有如下要求1）钢筋应尽可能采用螺纹钢筋，增加握裹力和止水能力2）钢筋接头应尽量采用焊接接头，尽量少用和不用绑扎接头4）严格控制钢筋保护层厚度

2.3混凝土的拌制和运输由于防水混凝土要求较高的密实性，所以拌制也要有较好的均匀性，为此应做好如下儿点1）确保搅拌时间，每次搅拌从投料到出料一般不少于2mine2）当使用外加剂，应将外加剂制成一定浓度的溶液后加入搅拌机内，不得将外加剂的干粉或高浓度溶液直接加入搅拌机内，防止搅拌不均匀而局部集中，既失去外加剂作用，又影响混凝土质量3）施工过程中应定期抽查测定混凝土坍落度，施工中如遇下雨或其他原因，砂石含水量发生变化时，应及时测定其含水率，并调整施工配合比4）本工程使用商品混凝土，有效的提高了混凝土搅拌质量及各类外加剂的掺量，严格控制了混凝土水灰比及坍落度5）混凝土的浇筑采用泵送工艺，有效的避免了混凝土在运输过程中产生离析泌水及漏浆现象

2.4施工中的注意事项1）施工作业面的合理划分2）严格做到定点定量下料根据分层浇筑高度和运输工具的车容量，严格进行定点定量方可下料，这是提高防水混凝土浇筑质量的重要一环3）坚持开门子下料或用串桶（溜槽）下料4）混凝土的振捣是保证混凝土密实、防渗的重要一环，点定量均匀下料的基础上，也应采取定点振捣，精心操作注意上下层的衔接，既要防止漏振、欠振，又要防止过振，特别要禁止用撬动钢筋或振动钢筋来助振的方法，这样将使前面已浇筑振实部分的钢筋与混凝土分离，造成严重后果5）认真做好接浆措施，及时调整坍落度

2.5施工缝作法施工缝是防水结构的薄弱环节之一应尽量少留或不留，当混凝土浇筑受到设备或支模条件的限制时，则可在征得设计单位的同意后，在规定部位留置水平施工缝，一般留在底板以上200nun处的竖壁上工程中采用新工艺一一膨胀性橡胶止水带处理施工缝的方法，取代常用方法，诸如企口式施工缝、高低式施工缝、平口施工缝等防水混凝土一般在垂直方向不留置施工缝，在主楼与裙楼之间设了后浇带，垂直方向的施工缝在接缝部位设置膨胀性橡胶止水带或钢板止水带由于施工缝是防水结构的一个薄弱环节，施工中应专人负责，精心操作，确保施工质量采用止水钢板时不得有漏焊，采用橡胶止水带在接长时务必要将接头用专用胶水粘贴牢固可靠

2.6混凝土的养护与拆模防水混凝土浇筑后养护工作的好坏，不仅影响到混凝土的强度，而且影响到混凝土的抗渗性能试验证明，防水混凝土早期脱水或养护过程缺水，将大幅度降低其抗渗性能防水混凝土养护应不少于14d防水混凝土拆模要求也比较高，拆模时间不宜过早，拆模时应精心操作，防止用铁棍撬，大锤猛敲硬撬，使混凝土遭到破坏

2.7做好回填土结束语以上对混凝土的施工温度与裂缝之间的关系进行了理论和实践上的初步探讨，虽然学术界对于混凝土裂缝的成因和计算方法有不同的理论，但对于具体的预防和改善措施意见还是比较统一，同时在实践中的应用效果也是比较好的，具体施工中要靠我们多观察、多比较，出现问题后多分析、多总结，结合多种预防处理措施，混凝土的裂缝是完全可以避免的参考书目（略）Discuss the construction temperature and crack of the concrete lightlyThe summary,In order to prevent the ownersof the concrete workof claims,we mustdo agood jobin the construction processin the temperature andcrack control,through observationlive formany years,through consultingthe monographabout stresswithin the concrete,explain toconcrete temperaturereason,on-the-spot concretecontrol andmeasure,prevention of crack oftemperature thatcrack produce.Keyword ConcreteTemperature stressCrack Control

1.The concreteoccupies theimportant position in modernengineering construction.But today,the crack of the concrete iscomparatively general,the cracksare nearlyomnipresent in the scienceof bridgebuilding.Though wetake variouskinds ofmeasures in constructing,careful,but the crack stilloccurs nowand then.Tracing itto itscause,it is one of them incompletelythat ourchange toconcrete temperature stress paysattention to.In thelarge volumeconcrete,temperature stress and temperaturecontrol aresignificant.This ismainly because of thereason oftwo respects.First of all,concrete oftenappear the temperature crack in notconstructing,influence theglobality anddurability of the structure.Secondly,in thecourse ofoperating,the temperature change hasremarkable influencethat cantbe ignoredon thestress stateof thestructure.We meetto constructtemperature crackin mainly,so onlyto origincause offormation andtreatment measure,concrete ofcrack makea discussioninconstructingthis text.Reason of a crackHave manykinds ofreasons toproduce the crackin the concrete,it ismainly the changes oftemperature andhumidity,fragility anddisparity of the concrete,and thestructure isunreasonable,the rawmaterials isnot upto standardif thealkali aggregatereact,the templateis outof shape,the foundationdoes notsubside etc.evenly.Analysis of2temperature stressesCan bedivided intofollowing threestages accordingto theforming processof the temperature stress:1It isearly:Build concreteis it is itover basicallyto sendout heatto cementto begin,generally oneone dayby oneself.Two characteristicsat thisstage,first,the cementemits alarge amountof heatof hydration,second,mix andcongeal thechanging sharplyof elasticmodel quantity.Because of thechangeof elasticmodel quantity,form theremaining stressin the concrete in this period.2Middle period:Up tillthe concreteis cooleduntil stabilitytemperature fromcement sendout heatfunction basicallywhen expiring,inthis period,the temperaturestress ismainly because the coolingof the concrete andexternal temperaturechange cause,these stressesand remnantsstresses thatis formedin earlydays aresuperposed,mix andcongeal theelastic mouldamount thatgoes toand doesnot changemuch duringthisperiod.3Later period:Operation periodafter thecomplete coolingof concrete.Temperature stresswhether external temperaturechangecause mainly,these stressesand firsttwo kinds of remnantsstresseses arechanged andadded.Control andpreventing the measure of thecrackof3temperature Forprevent crack,lighten temperaturestress canfrom controltemperatureandis itis itset aboutto restrainterms fromtwo toimprove.The measure of controllingtemperature isas follows:1Is itimprove aggregategrade mix,is itdo rigidconcrete tospend,mix mixtureto adopt,is itguide angrypharmaceutical orplastification pharmaceutical,etc.measure in orderto reduce cement consumption of concrete toadd;2Add wateror the water tocool thebroken stonein orderto reduce thetemperature of buildingof the concrete whilemixing andshutting the concrete;3Reduce thethickness ofbuilding whilebuilding theconcrete onhot day,utilize andbuild theaspect todispel theheat;4Bury the water pipeunderground in theconcrete,enter thecold waterto lowerthetemperatureopenly;5Stipulate rationalform removaltime,thetemperaturekeeps warmthe surfacewhile loweringsuddenly,in casethat therapid temperature gradient takesplace intheconcrete surface;6The concretewith mediumand long-term andexposed constructionbuilds apiece of surface orthin wallstructure,take the measureofkeeping warmin coldseason;The measureof improvingcondition ofrestraining is:1Divide andsew anddivide onerationally;2Prcvent thefoundation fromrising andfalling too big;3Rational arrangementconstruction process,prevent thetoobigdiscrepancy inelevation andside fromexposing fbra long time;In orderto guaranteeconcrete projectquality,prevent fracturing,improve thedurability of theconcrete,usetheadmixture to reduce one ofthemeasures thatfractures correctly.Whether is it reduce water is it split pharmaceutical to defend,I summarizehis mainfunction inpractice to use.1There ispore Daoofalarge numberof maointheconcrete,produce capillarytension inthe capillaryafter wateris evaporated,make concreteis itcontract outof shapeto do.Increasing thethin apertureof haircan reducethe capillarysurface tension,but willmake the intensity of concrete reduce.This surfacetension theoryhas alreadybeen confirmedintheworld as far backas thesixties.2Water dustthan influenceimportant factorthat concreteshrink,is itreduce wateris itsplit pharmaceuticalcan makeconcrete waterconsumption reduceby25%to defendtouse.3Cement consumptionimporlant factor,concrete ofperson whoshrink too,is itadd andsubtract wateris itsplit concretereducible15%ofthecementconsumptionon termsthat keeptheintensityof concreteof pharmaceuticalto defendto mix,its volumeis supplementedby increasingaggregate consumption.4Reduce wateris itsplit pharmaceuticalcan improveconsistency ofgrout,reduce concretesecrete inkto defend,reduce andsink anddraw backdeforming.5Improve glueingthe strengthof formingofthegrout andaggregate,theconcreteimproved resiststhe performanceof splitting.6Concrete is it producestress ofdrawing torestrain fromwhile shrinking,crack whendrawing thestressandis greaterthan concretetensile strengthcan produce.Reduce waterisitsplitpharmaceuticaleffective concretetensile strengthof improvementvery todefend,improve resistingthe performanceof splittingof concreteby a wide margin.7It canmake theconcrete densitygood toadd theadmixture tomix,can improveresisting carbonizationof concreteeffectively,reduce carbonizationto shrink.8Is itreducewaterisitsplit slowcoagulation timeproper concreteunder pharmaceuticaltodefend,on thebasis ofpreventing thefast waterof cementfrom sendingout heateffectively tomix,prevent theplasticity shrinkthat bringsbecause thecement isnot congealedfor alongtimefrom increasing.9Mix admixtureconcrete andgetting easyand kind,surface easyto feelflat,form littlemembrane,reducethemoisture toevaporate,reduce drilyand shrink.A lotof admixtureall havethe functionsof slowcoagulation,increasing andapt,improvement plasticity,the experimentthat weshould carry oninthis respectmore inthe projectpractice iscompared with and studied,than leanagainst notimproving termsmore simple,may gettingsimple andmore direct,economy.Early maintenanceof4concrete Practicehas proved,the commoncrackofconcrete,most isthe surface crackofdifferent depth,main reasonits whethertemperaturegradientcause coldtemperatureofarea lowertoo easyto formcrack suddenly.So saythe warm-keeping oftheconcreteis especiallyimportant to preventing theearly crackofsurface.From theviewpoint oftemperaturestress,should reachand requireto keepwarm followingly:1Prevent concreteinternal andexternaltemperaturepoor andconcretesurfacegradient from,preventthesurfacecrack.2Prevent concretefrom to be ultraand cold,should isitisit makethe minimumtemperature isnot lowerthan thesteady temperatureofconcreteservice timeconstruction timein concrete to tryto try ones best.3Prcvent theold concretesubcooling,in ordertoreducethe restraintamong theold andnew concrete.

2.Quality controlof waterproof concrete constructionCombined withexperience,from formworkdesign,fabrication andinstallation,assembing reinforoement,pouring and curing ofconcrete andother aspectsconstruction technologyof fair-faced concreteis introducedas wellas qualitycontrol measuresand standardsinordertoreduceengineering costto acquiresatisfied economicand socialbenefits.Method being under construction

2.1Fabrication andInstallation Accordingto theconcrett ofclosely knit,demand ofreason whyto form board sincethewater-proof alsoconcrete havemade andhave assembledcorresponding riseis special,be torequire thatnot leavingout thickfluid,firm closelyknit block of wooddeformation,water absorptionCharacter should be smalland oughtto givepriority toselect andusing bambooslab rubberform boardor thesteel form..Strict controlformboardroom gapsize,necessary exceeding2mms usesfoam rubberor plasticto squeezea crackin,porous formboard nonutilitywithout exceptionto boardface Beready forwall postat thesame timerotting theprevention andcure jobAdopt thecement mortarpouring same,indicia inbefore theroot segmentsticking thefoam rubberor plasticstrip,the bottomputs ona cementmortar,concrete a concrete,first5cm~10cm.Since water-proof,concrete structurewall thicknessis mostlymore infertile.Be toensure thatcomponent geometrydimension,Chang adoptthe insideand outsidebolt topull themeasure meetingattention to,responds toon playreceive boltcentre interposestop wateriron plate,to preventwater fromforming pilotagepassage alongbolt leakage.

2.2Assembing reinforoementWater-proof concretestructure hasdemanding asfollows to the reinforced bar1reinforced barshould adopttwisted steelasfaras possible,increases byhold wrapa forcecomposing inreply awater ability2reinforced barsconnect shouldtryone*s bestto adoptto solderconnection,stop usingand beingneedless tobind connectionto thefull3when bindinga reinforcedbar,the ironwire headresponds toinner bending.4strict controlreinforced barsprotective layerthickness.The concretestirring andmixing makesand transportsSince thewater-proof concreterequires thathigher closelyknit,reason whystir andmix systemalso needto havethe fairlygood homogeneity,shouldbeready forburning asfollows almostfor thispurpose1ensures thatmixing time,mixing atevery timeare secondaryjump intoa expectthe generalejection ofcompact blockof wood less than2mins.2should usethe appositionagent,the solutionqueen whoshould manufacturecertain thicknessfrom appositionagent adds the mixer inner,the driedpowder orhigh concentrationsolution willadd anagent extranot toaddsthemixerinnerdirectly,prevent frommixing isuneven butpart concentrates,both losethe appositionagent effect,and affectconcrete mass.3responds to the assured source of life degreehaving aspot teston theadmeasurement concreteat theregular intervalscollapsing inthe processbeing under construction,construction ismiddle ifYu rainsor othercause,respond to the ratiodetermining whosewater ratio,and adjustingthe compositionbeing underconstruction intime whenchange happenedin sandstonemoisture content.4project usesthe commodityconcrete,has boundaryhave raiseda concretestirring massand ofall kindseffect appositionagent adulteratingfalls whenamounts,thewaterash havingcontrolled aconcrete strictlycollapsing.5concretes concreteadopt apump tohave givenhandicraft,effective avoidingaconcreteproducing thephenomenon isolatingMi Shuiand leavingout thickfluid inthe processof transportation.

2.4Matters needingattention inbeingunderconstruction1construction schoolassignment softand flouryis divided.2Achieve strictlyfixed pointdetermines the amounts ofthe components ofa substance materialdown Accordingtothevehicle capacitiesstratifying concretealtitude and the meansof transport,the quantifycarrying outfixed pointstrictly isable togo downone important ring expecting that thisis toimprove water-proof concretingmass.3insist thatyou godown materialopening thedoor oruse stringto expectthat underbarrel chuteBeto preventa cementpaste fromparting fromaggregate for,to expectthat libertyshould notexceed

1.5ms nowand thenhighly underwater-proof concreteo4concretes vibratingbeat oneimportantringbeing toensure that theconcreteis closelyknit,defend againstto seepwithastick.Also,should adoptfixed pointvibrating,handle meticulouslyon basisexpectingthatunder determiningtheamountsofthecomponentsofasubstancehomogeneously infixed point.Pay attentionto highand lowtier oflinking upNow thatneeding toprevent frommiss andvibrating,not vibratingenough,being goingtopreventa faultfrom vibratingagain,Need toforbid usingprying themethod comingto aidto vibratemoving a reinforcedbaror shakingareinforcedbar especially,such separatesto makingthe frontalready concretethe reinforcedbar andconcrete shakingthe realitypart,causes seriousconsequences.5being readyfor theassuredsourceoflifedegree takingover thickfluid measure,adjusting intime tocollapse seriously.

2.5The methodof Constructionjoint The construction joint isoneof water-proof architecturalweak link.Theconstruction jointisoneof water-proof architecturalweak link.Should stopstaying ornot stayingtothefull,equipment orprops upconditional restrictingof model,may thenbehind theagreement collectinga designorgan,on thewall stipulatingthat lienablelevel oflocation construction joint,sort keepvertical strokesgetting alongin allabove200bottom board.Adopt newhandicraft expansibility intheproject rubberwater justbrings handlingtheconstruction joint method,substituting methodin commonuse,anxiously expectingthe dyadicconstruction jointof mouth,at anyrate dyadicconstructionjoint,flat mouthconstructionjointsuch asand soon.Water proofingis inno lienableconstructionjointof perpendicularitydirection liketheconcrete,rubber stopsin havingset uptheconstructionjoint irrigatingbelt,perpendicularity directiontheday afertomorrow betweenthe mainbuilding andthe skirtbuilding interposingexpansibilityinseam locationwater beltor steel plate stopswater belt.weak linkofwater-proof structure,respond tospecially-assigned personconscientiously,handle meticulously.Ensure massto beunderconstructionin construction.Adopt tostop havingnot tomiss andnot solderingtime watersteelplate,adopt rubberwater beltjust shouldbe solidwithout failreliably inreceiving longtime willconnect usingspecial useglue topaste.When onlythink thatconcreting accepts

2.6Dismantling modelandcuringofconcreteThe water-proof concretingqueen maintainsgoodness andbadness working,not onlyaffecting theintensity arrivingat aconcrete,moreover theimpervious functionaffecting totheconcrete.Evidence,water-proof concreteearly phasedehydration orcuring processlack forwater,will reducewhose imperviousfunction byawidemargin.Water-proof concretecuring respondstotheblockofwoodlessthan14ds.The water-proofconcretedismantles a model demandingtobeunable tocompare high,dismantle modeltime unsuitableuntimely,respond towhen dismantlingamodelhandle meticulously,prevent aniron rodfrom usingto pry,stiffly,that thesledgehammer isknocked suddenlyand forciblypries,uses aconcrete meetwith destroy

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21.浅谈混凝土的施工过程中温度与裂缝控制B摘要为了防止业主对混凝土工程的索赔，就必须做好施工过程中温度与裂缝控制本文通过多年的现场观察，通过查阅有关混凝土内部应力方面的专著，对混凝土温度裂缝产生的原因、现场混凝土温度的控制和预防裂缝的措施进行等进行阐述关键词混凝土；温度应力；裂缝；控制混凝土在现代工程建设中占有重要地位而在今天，混凝土的裂缝较为普遍,在桥梁工程中裂缝几乎无所不在尽管我们在施工中采取各种措施，小心谨慎，但裂缝仍然时有出现究其原因，我们对混凝土温度应力的变化注意不够是其中之一在大体积混凝土中，温度应力及温度控制具有重要意义这主要是由于两方面的原因首先，在施工中混凝土常常出现温度裂缝，影响到结构的整体性和耐久性其次，在运转过程中，温度变化对结构的应力状态具有显著的不容忽视的影响我们遇到的主要是施工中的温度裂缝，因此本文仅对施工中混凝土裂缝的成因和处理措施做一探讨

1、裂缝的原因混凝土中产生裂缝有多种原因，主要是温度和湿度的变化，混凝土的脆性和不均匀性，以及结构不合理，原材料不合格（如碱骨料反应），模板变形，基础不均匀沉降等

2、温度应力的分析根据温度应力的形成过程可分为以下三个阶段

（1）早期自浇筑混凝土开始至水泥放热基本结束，一般约30天这个阶段的两个特征，一是水泥放出大量的水化热，二是混凝上弹性模量的急剧变化由于弹性模量的变化，这一时期在混凝土内形成残余应力

（2）中期自水泥放热作用基本结束时起至混凝土冷却到稳定温度时止，这个时期中，温度应力主要是由于混凝土的冷却及外界气温变化所引起，这些应力与早期形成的残余应力相叠加，在此期间混凝上的弹性模量变化不大

（3）晚期混凝土完全冷却以后的运转时期温度应力主要是外界气温变化所引起，这些应力与前两种的残余应力相迭加

3、温度的控制和防止裂缝的措施为了防止裂缝，减轻温度应力可以从控制温度和改善约束条件两个方•面着手。