專業(yè)英語翻譯

專業(yè)英語翻譯DiscusstheconstructiontemperatureandcrackoftheconcretelightlyThesummary,throughobservationliveformanyyears,throughconsultingthemonographaboutstresswithintheconcrete,explaintoconcretetemperaturereason,on-the-spotconcretecontrolandmeasure,preventionofcrackoftemperaturethatcrackproduce.KeywordConcreteTemperaturestressCrackControlTheconcreteoccupiestheimportantpositioninmodernengineeringconstruction.Buttoday,thecrackoftheconcreteiscomparativelygeneral,thecracksarenearlyomnipresentinthescienceofbridgebuilding.Thoughwetakevariouskindsofmeasuresinconstructing,careful,butthecrackstilloccursnowandthen.Tracingittoitscause,itisoneofthemincompletelythatourchangetoconcretetemperaturestresspaysattentionto.Inthelargevolumeconcrete,temperaturestressandtemperaturecontrolaresignificant.Thisismainlybecauseofthereasonoftworespects.Firstofall,concreteoftenappearthetemperaturecrackinnotconstructing,influencetheglobalityanddurabilityofthestructure.Secondly,inthecourseofoperating,thetemperaturechangehasremarkableinfluencethatcan'tbeignoredonthestressstateofthestructure.Whomwemeettoconstructtemperaturecrackinmainly,soonlytoorigincauseofformationandtreatmentmeasure,concreteofcrackmakeadiscussioninconstructingthistext.1、ReasonofacrackHavemanykindsofreasonstoproducethecrackintheconcrete,itismainlythechangesoftemperatureandhumidity,fragilityanddisparityoftheconcrete,andthestructureisunreasonable,therawmaterialsnotuptostandard(ifthealkaliaggregatereact),thetemplateisoutofshape,thefoundationdoesnotsubsideetc.evenly.Thecementemitsalargeamountofheatofhydrationwhentheconcreteishardenned,insidetemperatureisrisingconstantly,causethestressofdrawingonthesurface.Inthecourseofloweringthetemperature,isitcongealfoundationpayrestraintomixalwayslaterstage,willpresentthestressofdrawingwithintheconcrete.Reducingoftemperaturecansurfacecauseheavystressofdrawingveryinconcretetoo.Whenthesedrawthestressandgobeyondresistingtheabilityofsplittingofconcrete,namelywillpresentthecrack.Alotofinsidehumidityofconcretechangeverylightorchangerelativelyslow,surfacehumiditymightchangeheavytheviolentchangetakesplacing.Suchasmaintainingthoroughly,whengettingwetterwhennotdoing,contractsurfacetherearen'tdeformationdoing,oftencausethecracktoo.Theconcreteisakindoffragilitymaterial,tensilestrengthisabout1/10ofthecompressionstrength,isitcarryonone'sshoulderorbacklimitwhendrawoutofshapetohave*104only,isitcarryonone'sshoulderorbacklimitlocationwhenstretchoutofshapetothereis*104toaddforalongtimetoaddashorttime.Becauserawmaterialseven,waterdustthanunstable,transportandbuildphenomenonofemanatingofcourse,itstensilestrengthisnoteveninthesameconcrete,alotofresisttheabilityofdrawingverylow,itisapttopresenttheweakpositionofthecrack.Amongarmoredconcrete,drawstresstoundertakebyreinforcingbarmainly,concretebearstressofkeepingjust.Orreinforcingbarmixifedgepositiongonetotocongealpresentthestressofdrawinginthestructureinplainconcrete,mustrelyontheconcreteoneselftobear.Requiretoavoidthestressofdrawingoronlyverysmallstressofdrawingappearsofthethegeneraldesign.Buttheconcreteiscooledfrommaximumtemperaturetothesteadytemperatureofoperatingperiodinconstructing,oftencausesizabletodrawthestresswithintheconcrete.Thetemperaturestresscanexceedotheroutsidesandloadthestressescausedsometimes,knowchangelaw,temperatureofstressforcarryonreasonablestructuraldesignandconstructextremelyimportant.2、Analysisof2temperaturestressesCanbedividedintofollowingthreestagesaccordingtotheformingprocessofthetemperaturestress:(1)Itisearly:Buildconcreteisitisitoverbasicallytosendoutheattocementtobegin,generallyoneonedaybyoneself.Twocharacteristicsatthisstage,first,thecementemitsalargeamountofheatofhydration,second,mixandcongealthechangingsharplyofelasticmodelquantity.Becauseofthechangeofelasticmodelquantity,formtheremainingstressintheconcreteinthisperiod.(2)Middleperiod:Uptilltheconcreteiscooleduntilstabilitytemperaturefromcementsendoutheatfunctionbasicallywhenexpiring,inthisperiod,thetemperaturestressismainlybecausethecoolingoftheconcreteandexternaltemperaturechangecause,thesestressesandremnantsstressesthatisformedinearlydaysaresuperposed,mixandcongealtheelasticmouldamountthatgoestoanddoesnotchangemuchduringthisperiod.(3)Laterperiod:Operationperiodafterthecompletecoolingofconcrete.Temperaturestresswhetherexternaltemperaturechangecausemainly,thesestressesandfirsttwokindsofremnantsstressesesarechangedandadded.Canbedividedintotwokindsaccordingtothereasonwhythetemperaturestresscauses:(1)Spontaneousstress:Therearenotanyrestraintortotallystaticstructureattheborder,ifinsidetemperatureisnon-lineardistribution,temperaturestressappearingbecausestructurerestrainsfromeachother.Forexample,thebodyofmoundofthebridge,thephysicaldimensionisrelativelylarge,surfacetemperatureislowwhentheconcreteiscooled,insidetemperatureishigh,presentthestressofdrawingonthesurface,presentthestressofpressinginthemiddle.(2)Restrainthestress:Allofthestructureonesoritrestrainexternalonesomeborder,can'toutofshapeandstressnotcausenotfree.Suchascaseroofbeamroofconcreteandguardrailconcrete.Thistwokindsoftemperaturestressesdrawbackstressescausedtoactonwiththedoingofconcretetogetherfrequently.Itisamorecomplicatedjobtowanttoanalysethedistribution,sizeofthetemperaturestressaccuratelyaccordingtoknowntemperature.Incaseofgreatmajority,needtorelyonthemodeltestorthenumbervaluetocalculate.Toisitmaketemperaturestresshavesizablelimptocreepconcrete,atthestressaccountingtemperature,mustconsidertheinfluencethatcreep,calculateconcretlythatnolongerstatesthinlyhere.車3直、別Contro悶land停preven派tingt番hemea卸sureo諸fthe篩crack必of3t矩empera趣ture蠢Forpr湯event苦crack仰,ligh戰(zhàn)tente米mperat智urest室ressc臥anfro件mcont丘rolte燥mperat果urean季disi今tisi帆tset容about違tores榴train粗terms幕fromt囑woto債improv旬e.蹤Theme悟asure時ofcon凡trolli腿ngtem膛peratu吃reis薪asfol墻lows:喊(刪1)Isi玻timpr秒oveag無gregat暮egrad盲emix甜,isi鋪tdor邪igidc煮oncret曠etos堤pend,喜mixm蔬ixture靠toad駕opt,i謠sitg零uidea酬ngryp功harmac畏eutica交lorp尋lastif賓icatio閘nphar娘maceut柱ical,率etc.m拾easure晶inor聰derto勁reduc熟eceme夕ntcon妥sumpti福onof冤concre巧teto軋add;木(唐2)Add燙water莊orthe雙water陽toco吳olthe押broke趟nston連eino志rdert形oredu仔cethe辱tempe趨rature湖ofbu票ilding陳ofth滲econc識retew繭hilem傭ixing渠andsh洽utting走thec傷oncret投e;忍(鞏3)Redu午cethe雞thick石nesso嫩fbuil豐dingw顯hileb促uildin票gthe培concre紗teon涂hotda晨y,uti緞lizea理ndbui嫁ldthe隆aspec企ttod質ispel續(xù)thehe辦at;失(算4)Bury察thew匠aterp委ipeun洲dergro狗undin豆thec匯oncret嗓e,ent牛erthe冬cold天water姨tolow題erthe選tempe崗rature蜓openl距y;百(銹5)Stip濤ulate漂ration讓alfor磚mremo框valti練me,th筍etemp罷eratur饞ekeep地swarm霉thes返urface歌while挨lower方ingsu密ddenly慎,inc恩aseth軟atthe匯rapid吉tempe沖rature插gradi舒entta困kespl姻acein蔑thec姻oncret脅esurf清ace;惑(餐6)The炭concre漏tewit棚hmedi歌umand僻long-餐terma娛ndexp搶osedc晴onstru哈ction疼builds莖apie泉ceof炮surfac竭eort凝hinwa隙llstr棚ucture有,take里them戚easure毀ofke網(wǎng)eping酸warmi命ncold橫seaso爸n;游Theme音asure涂ofimp遵roving薪condi武tiono前frest溫rainin移gis:掉(拿1)Divi辯deand事sewa循nddiv天ideon孝erati菊onally濱;耍(螺2)Prev泳entth欄efoun栗dation勤from南rising點andf樸alling申toob濱ig;私(伍3)Rati滴onala躬rrange年mentc酒onstru霸ction市proces真s,pre黑ventt策hetoo登bigd絞iscrep德ancyi諸nelev抽ation醋andsi話defro柳mexpo領singf卷oral址ongti存me;辜Inadd員ition,協(xié)impro劍vethe銜perfo號rmance撕ofth凝econc耕retea繞ndimp文rovea林ndres返istth扎eabil個ityof堡split蒼ting,替streng寬thenm是ainten猛ance,領preve炸ntthe陸surfa遲cefro匙mbein死gdone蔑andc劍ontrac獲ted,刺especi悅allyg縣uarant恰eethe異quali床tyof極theco寇ncrete嘆isve食ryimp稅ortant意topr閃eventi隨ngthe決crack丈,shou茫ldpay滴speci濤alatt捐ention旨toav喂oiding滑produ街cinga蝴ndrun籃ningt逆hrough凱thec私rack,智theg配lobali敢tyres暖umedi袖tsstr表ucture極after喪appea偶ringi躺svery寬diffi昏cult,券sosho珠uldre秋lymai完nlyon掘preve虛nting計theem課ergenc柔eoft獄herun腳ningt剝hrough往crack圍while悟const解ructin檔g.剖Incon步struct監(jiān)ionof丸concr狗ete,炭forra傅isetu魯rnover查rate運oftem閥plate低,dema品ndcon怪crete莖formr蓋emoval瘦asso拼onas遭possib質letha北tbuil跡dnewl覆yofte陪n.Sho偵uldco暮nsider話form枝remova溉ltime貨prope蹈rlywh糖encon設crete平temper劇ature延ishig亦herth糞anthe采tempe論rature侮,soa逗snot伴tocau驟sethe承super撒ficial角early賓crack康ofco護ncrete航.Buil駱dingt險heear記lyfor爸mremo驢valne育wly,c聯(lián)ausev裕eryla斯rgest預resso武fdraw澤ingon停thes好urface撞,the巡phenom宿enont滅hat"功temper箱ature壘isass千aulted覽"app鈔ears.柱Build道initia忽lstag甚einc壩oncret著e,bec令auseh煙eatof男hydra印tioni江ssent僚out,刻thesu痛rface深causes芹sizab邪l(fā)eto股drawt狐hestr窄ess,s霞urface兇tempe瓜rature命isal暖sohig延herth箱antem敢peratu受reat豎thism假oment,惜remov蟻ethe脈templa違teat巴thism愛oment暮,surf蘆acete向mperat槍ureis層lower柳edsud筒denly,框must御cause釣temper梨ature道gradie帶nt,t組husad療dand屠drawt增hestr瓣esson調thes愈urface女,cha幟ngean挑dadd鼓witht細hehea鞋tofh啦ydrati璃onstr博ess,i淡naddi搭tion,覺theco恐ncrete驗dries趕andc祥ontrac團ts,t缺hesup燃erfici移alstr壁essof刻drawi豆ngrea罷chesv答erygr江eatnu苗mberv爭alue,膠haved亭anger塊ofcau卵singt悼hecra高ck,bu附tcove炭rali煎ght-du紙tyhea趟tinsu應lator危witho晶nthe激surfac憶eint薯imeaf逆terre衛(wèi)moving森thet賄emplat璃e,fo角rinst朵ancef鄰oamsp房onge,差etc.,擁forpr絮event畫concre血tesur迫facef蒼rompr蜂oduce眼theto懼obig喂stress章ofdr扒awing,殊have樹remark色abler挽esults話.個Addmu斧sclei凝nfluen快ceto痕large福volume午tempe設rature神stres兩sofc倒oncret烈every筒light廁,bec里ausel紫argev饑olume丹concre爺teinc撕ludem撞uscle虛tobe讓ratev撲erymu靠chlow井.Just紡have稀influe返nceon擔theg譯eneral獻armor帥edcon桌crete.斷Onte爸rmsth夾attem屢peratu先reis炒notve縣ryhig難hand凈thest夕ressi冶sless靠than駝limit濫ofsur限r(nóng)ender吃ing,e率veryp蛋erform輕anceo運fthe踏steel惕isste替ady,a矛ndhav而enoth傻ingto努dowi這thstr雹essst縮ate,男timea滔ndtem孩peratu足re.Li吳neblo剝atedc慢oeffic慨iento銳fstee座land丟concre慎telin繭ebloa睛tedco羊effici瓜entdi靜fferen倘cever儀yligh匠t,tak你eplac祖elitt緒leint胳ernal謝stress戴very勾onlyb業(yè)etween堆thet箱wowhi毛lecha郊nging耽intem編peratu矮re.Be牽cause勾elasti刺cmoul跡damou度ntof閑steel露concre忌teela花sticm寒ould7遺~15of痕quant牌ity,r尋eacha集sinte緞riorc奮oncret繡estre挖ssten賞siles臣trengt販hand唉whenf逗ractur續(xù)ing,t湯hestr坊essof慨ther永einfor榆cingb鷹arwil虛lnot關exceed據(jù)質10000k嘉g屠/cm2.德.Soi博siti框sitp為revent能tiny地appear極anced練ifficu渠ltyve連rymuc靈hofc音rackf術romto濱make兔useof療reinf瓦orcing趕bart裙owant躺among冊concr罵ete.B沙utthe酬crack為inth雕estru些cture左genera蘆llybe胃comes計numero秒us,th杰einte磁rvali噸slitt扒le,th腳ewidt裝hand盛depth弄aresm蠶aller掠after盯adding啞them叫uscle.痰Andi四fdiam址etero擊frein饅forcin宴gbar淹detail輸edand吵when通interv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