简介:在相等的压缩力量的前提上把臼的力量弄弯上的矿物质混合的影响被调查。三矿物质混合(苍蝇灰,扎根的成粒的强风炉子炉渣和钢炉渣)被使用。在这研究的矿物质混合的增加的数量从22.5%~60%,并且water-to-binder比率从0.34~0.50。与相等的压缩力量,不同的臼能与他们的弯曲力量在如此的一份下降订单被安排:水泥苍蝇灰臼,水泥臼,cement-GGBS臼,和水泥钢炉渣臼。与一样的压缩力量,越高钢炉渣内容和water-to-binder比率,越多降低臼的弯曲力量。然而,矿物质混合内容的效果和水泥苍蝇灰臼和cement-GGBS臼的弯曲力量上的water-to-binder比率是远不引人注目的。
简介:SinceOctober2008,China'ssocialconsumptionofelectricityhad,forthefirsttime,grownnegativelycomparedtothesameperiodofthepreviousyear,andinNovemberthenegativegrowthrangefurtherexpanded.Themajorpressurefacedbytheelectricityindustryhasnowturnedfromthecontradictionbetweencoalandelectricitytoelectricityquantity.Thisisundoubtedlyatrueandnewtesttoelectricityenterpriseswhichgetusedtohighgrowthbutarenowsufferinggreatlosses.Thereformofelectricit...
简介:Theseismicperformanceoffourshortconcretecolumnswasinvestigatedunderlowcycleandrepeatedloads,includingthefailurecharacteristics,hystereticbehavior,rigiditydegeneracyandsteel-barstress.Theinfluencesofreinforcementstrength,stirrupratioandshearspanratiowerealsocompared.Testresultsrevealthattherestrictioneffectofstirrupscanimprovethepeakstress,sothebearingcapacityofspecimencanbeimproved;forthehigh-strengthshortconcretecolumnwithhigh-strengthstirrups,itwasmorereasonabletouseultimatedisplacementangletoreflecttheductilityofthespecimen,andtheyieldstrengthofhigh-strengthstirrupsshouldbedevaluedwhencalculatingthestirrupcharacteristicvalue;theseismicperformanceofshortcolumnwouldbeimprovedwiththeincreaseofvolume–stirrupratioandshearspanratio;thehigh-strengthstirrupsandhigh-strengthlongitudinalreinforcementsdidnotyieldwhentheloadactingonthespecimenreachedthepeakvalue,whichbroughtadequatesafetystocktotheseshortcolumns.
简介:Globalstrengthisasignificantitemforfloatingproductionstorageandoffloading(FPSO)design,andsteelweightplaysanimportantroleinthebuildingcostsofFPSO.Itisthemaintasktoconsiderandcombinethesetwoaspectsbyoptimizinghulldimensions.Therearemanyoptionalmethodsfortheglobalstrengthanalysis.AcommonmethodistousetheABSFPSOEaglesoftwaretoanalyzetheglobalstrengthincludingtherulecheckanddirectstrengthanalysis.AndthesamemethodcanbeadoptedfortheFPSOhulloptimizationbychangingthedepth.Aftercalculationandoptimization,theresultsarecomparedandanalyzed.Theresultscanbeusedasareferenceforthefuturedesignorquotationpurpose.
简介:Inthiswork,compressive,flexuralandsplittensilestrengthtogetherwithcoefficientofwaterabsorptionofhighperformanceself-compactingconcretecontainingdifferentamountofFe2O3nanoparticleshavebeeninvestigated.ThestrengthandthewaterpermeabilityofthespecimenshavebeenimprovedbyaddingFe2O3nanoparticlesinthecementpasteupto4.0wt%.Fe2O3nanoparticleasaforeignnucleationsitecouldaccelerateC-S-HgelformationasaresultofincreasedcrystallineCa(OH)2amountespeciallyattheearlyageofhydrationandhenceincreasethestrengthofthespecimens.Inaddition,Fe2O3nanoparticlesareabletoactasnanofillersandrecovertheporestructureofthespecimensbydecreasingharmfulporestoimprovethewaterpermeability.Severalempiricalrelationshavebeenpresentedtopredicttheflexuralandthesplittensilestrengthofthespecimensbymeansofthecorrespondingcompressivestrengthatacertainageofcuring.Acceleratedpeakappearanceinconductioncalorimetrytests,moreweightlossinthermogravimetricanalysisandmorerapidappearanceofpeaksrelatedtohydratedproductsinX-raydiffractionresultsindicatethatFe2O3nanoparticlesupto4wt%couldimprovethemechanicalandthephysicalpropertiesofthespecimens.
简介:Subseaflowline跳线开关(FJ)是为湿油树,subsea管道和起床人库的基本连接部件,起在subsea生产系统的一个不能替代的作用。在FJ的安装期间,碰撞经常发生在FJ和另外的设备之间,它可以引起严重损坏。作为操作的水深度增加,而且,对象鹤和绞车一样的安装设备的要求将增加。在中国的深海的FJ安装的研究仍然在主要阶段,因此为深海的FJ的一个安装方法在这篇论文被建议。一个典型M形状FJ安装系统的有限元素模型被造模仿安装过程。分析结果证明为FJ设计的安装步为深海的FJ可行、有效。为了保证安装的安全,处理,为FJ的碰撞敏感的分析被进行,并且结果证明设置在合适的价值的pickupspeed是必要的,以便在安装避免碰撞过程。而且,FJ的机械特征在环境条件的一个范围下面在安装期间被调查,FJ的最大的压力总是发生在它的中央位置,这被发现。为安装设备的基本要求也通过主要安装步的分析被获得。
简介:Thestrengthoflightweightconcreteundertriaxialcompressivestressisstudiedexperimentallywiththeconcretetriaxialapparatusdesignedbytheauthors,andiscomparedwiththatofnormalconcreteunderthesamestressstate.Ninety-five100mmcubesundertwentystressratiosaretested.Ascomparedwithnormalconcrete,itisfoundthatnotonlythemultiaxialcompressivestrengthoflightweightconcreteissmall,butalsotheratioofthemultiaxialcompressivestrengthtotheuniaxialcompressivestrengthissmall.Theinfluenceoftheintermediateprincipalstressonthemultiaxialstrengthoflightweightconcreteisdiscussed.Thestrengthcriteriawhichareexpressedintheprincipalstressesandtheoctahedralstressesrespectivelyareproposed.
简介:Thediaphragmofsteamturbineisoneofthemainpartsofthepassageunitforairflowingandthediaphragmofsteamturbineisgenerallymadebywelding,butduringthecourseofwelding,somecracksoftenhavehappened,thesecracksthreatensafetyproductiononthespot,soitisnecessarytoanalyzethestrengthofsteamturbinediaphragmwithacrack.Forstudyingitsworkingconditionandperformancewithacrack,thethree-dimensionalfiniteelementmodel(FEM)withthesoftwareANSYS10.0isestablishedaccordingtotheactualworkingparameters.Withthemodel,thedeformationresultsandstressfieldresultsareanalyzedandthemaximumdisplacementandstressvaluearecalculated,meanwhile,themaximumstresschangewithcrackdepthofsteamturbinediaphragmisanalyzed.Itprovidesagoodfoundationforsolvingtheprobleminproduction.
简介:InthispaperanumericalanalysismethodcombiningFEMincementaltechniquewithlimitanalysisconceptisproposedforthestudyofthestaticstrengthofoffshoreplatformincollision.Largedeformationandplasticityareaccountedforandthelimityieldsurfaceexpressedbygeneralizedstressforatubularsectionisderived.ThemodifiedstiffnessmatrixofspacebeamelementisformulatedbyPlasticNodeMethod.Thebucklingbehaviorofbeamcolumnscanalsobetakenintoaccount.Itcantracethegenerationofplastichingesduringloadingandfinallytheultimatestrengthofoffshoreplatformagainstcollisionisobtained.
简介:TheZrcoatingwasdepositedontitaniumsurfaceusingthemagnetronsputteringtechnique.EffectsofZrcoatingonmicrostructureandmechanicalpropertiesofporcelainfiredtotitaniumhavebeeninvestigated.Theresultsshowthatinterdiffusionofelementsoccursduringporcelainfiring,andtheZrcoatingcaneffectivelyprotecttitaniumsurfacefromexcessoxidation.ThestrengthofbondzonewithZrcoatingdepositedfor1hourreaches29.7MPa,whichhasincreasedby26.4%ascomparedwiththatofbondzonewithoutcoating(23.5MPa).
简介:Thispaperpresentsaninvestigationonstrengthofcementdeepmixing(CDM)mixture.Fourtypicalworksofoffshoreorland-basedprojectsareintroduced.Withsamplesfromtheseprojectsandlaboratorytests,statisticalanalysisismadeontheincrementlawofthestrengthofcement-soilmixturewithdifferentamountofcement,andstrengthsunderdifferentworkingconditionsarecompared.Itisfoundthattheamountofcementinthecement-soilmixtureiscloselyrelatedtotheunconfinedcompressivestrengthofthemixture.Attheageof90d,theunconfinedcompressivestrengthofthecement-soilmixtureincreasedby0.054Mpa-0.124Mpawitheachcementincreasing10kg/m3inthecement-soilmixture,averagelyincreasedby0.085Mpa,whilethatattheageof120dincreasedby11%incomparison.Thequalityofthecement-soilmixtureshouldbecomprehensivelyevaluatedinaccordancewiththetrimmedaverageofstrength,coefficientofvariationandrockqualitydesignation(RQD)indicatorsofsamplingratio.
简介:压缩力量,氯化物穿入抵抗和二高效的水泥的微观结构不到三被检验治好条件。治好的条件包括治好的标准(SC),治好匹配(MC,哪个工具在温度治好的封上的具体标本控制了盒子)并且根据温度的发展法律裸体水泥(NMC)治好匹配在地点上在集体水泥测量了。结果显示在MC和NMC下面的水泥在SC下面比那显示出更高的抵抗到氯化物穿入。在MC下面的水泥在NMC下面比那些有稍微更低的氯化物穿入,但是在NMC下面的标本的压缩力量比在在56d的MC下面的那高。另外,在NMC和MC下面具体比在SC下面有更高早的力量,特别在早年龄。然而,治好在248白天影响水泥的压缩力量的条件的顺序是:SC>NMC>MC。
简介:NickeliscommonlycoatedontheouterleadsforT8metalpackage.Theleadselectrodepositedbyconventionaldullorbrightnickelover5μmatdirectcurrentfromWattbatharehardtopassthebendfatiguetestforthreetimes.Nickelelectrodepositedatmultiwaveformcurrentincludingdirectcurrent,singleanddoublepulsefromsulfamatebathcanimprovethebendfatiguestrengthofleads.Suchnickelplatinghasamultilayerstructure,itsmorphologyofsublayerscanbeclearlyseeninitscrosssectionwithSEM.Theelectrochemicalstudyshowsthatthesesublayershavedifferentcorrosionpotentials.ThebendfatiguetestofleadswithsuchplatingforT8metalpackageshowsthatthenumberofbendincreaseswiththedecreaseofaveragecurrentdensityofmultiwaveform,whichcanbeattributedtothereductionofeverysublayerthicknessandtheincreaseoflayernumbersunderthesameconditionoftotalthickness.
简介:Poly(methylmethacrylate)(PMMA),usedasdenturebasematerialsinden-tistry,hassomeinherentdefects,suchaslowertoughnessorhigherbrittlenesswhichisoneofthemainreasonsofthefractureofdenturebaseinclinical.Therefore,manyscientistshavefocusedonhighimpactstrengthdenturebasematerials.Inthispa-per,usingMethylmethacrylate-butadiene-styrene(MBS)asareinforcementagent,
简介:Withtheextensivelywideapplicationofadvancedhighstrengthsteels(AHSS)invariousfieldsfortheexcellentmechanicalproperties,theindustrialinterestonthedamageofAHSSisincreasingintherecentyears.Forthesemodernsteels,duetothecomplexmicrostructureandtherelevantdeformationmechanisms,thedamageconceptneedstobereexamined.Inthispaper,thedefinition,lengthscaleanddifferentmechanismsofdamageareintroduced.Bothexperimentalevaluationofdamageandthenumericaldamagemodelsarebrieflyviewedandcompared.Theapproachestoimprovethedamagetolerancearegivenintheframeworkofdamagetolerancedesignprinciple.