简介：

简介：

简介：

简介：Thestudyofthebehaviorofconcreteunderbiaxialstressesisessentialtothedesignofoffshoreconcreteplatforms.Usingthemultiaxialtestapparatusdevelopedbytheauthors,thedeformationandstrengthofconcreteunderbiaxialstressesarestudiedexperimentally.Basedonthetestdata,anendochronicdamageconstitutivemodelandafailurecriterionareproposed.Accordingtotheabovemodel,anincrementalnonlineariterativeprogrammeisdeveloped,andaplatesampleinplanestressstateisanalyzed.

简介：在最近的年里，几个研究组为对存在大楼的地震反应评价学习了分析方法的新一代。不过，许多重要开发仍然被需要以便定义更多的可靠、有效的评价过程。而且关于存在大楼，由于低知识水平，线性有弹性的分析是允许的唯一的分析方法，这应该被加亮。一样的代码(例如NTC2008，EC8)为地震需求的评估与行为因素把线性动态分析看作参考方法。这类分析基于一个线性橡皮的结构的模型题目到一个设计系列，由通过一个行为因素减少有弹性的光谱获得了。行为因素(在一些代码的减小因素或q因素)被用来减少从线性分析获得以便考虑非线性的结构的能力的有弹性的光谱纵标或力量。行为因素应该基于几个参数被定义，例如机械材料特征，结构的系统，不规则和设计过程影响地震非线性的能力。在实际应用程序，仍然有详细规则和为存在大楼足够的精确行为因素价值的明显的缺乏。在这个工作，造类型的主要存在RC-MRF的地震能力的一些调查被执行了。为了做地震力量的正确评估，要求，与力量协调的实际行为因素价值基于地震安全评价过程被建议了并且在意大利的地震代码与价值相比报导了，NTC08。

简介：钢的地震行为增强了高力量，高效水泥(SRHC)框架列通过16框架列的伪静电干扰实验被调查与各种各样砍跨度比率，轴的压缩比率，具体力量，钢比率和马镫比率。三种失败机制被介绍，有不同设计参数的试验性的hysteretic曲线和骨骼曲线的特征被讨论。列韧性和精力驱散是基于地震抵抗评估的份量上。研究结果显示SRHC框架列能承受韧性的极端适用的能力，而是能力，因为SRHC自然易碎物，精力驱散是劣等的。作为结果，轴的负担比率应该被限制，一些构造措施采用了，例如增加马镫比率。这研究在SPHC列的适用的能力上建立了效果因素。最后，为用曲折失败模式获得最终的适用的能力的一个算法基于一个修改飞机节假设被建立。作者也证实决定砍的baroclinic失败并且砍的方程结合失败基于轴的负担力量分发比率的累积。计算结果砍忍受能力因为不同失败模式在对试验性的结果的好同意。

简介：

简介：Thispaperdescribesaquasi-statictestprogramfeaturinglateralcyclicloadingonsinglepilesinsandysoil.Thetestswereconductedon18aluminummodelpileswithdifferentcrosssectionsandlateralloadeccentricityratios,e/d,(eisthelateralloadeccentricityanddisthediameterofpile)of0,4and8,embeddedinsandwitharelativedensityof30%and70%.Theexperimentalresultsincludelateralload-displacementhysteresisloops,skeletoncurvesandenergydissipationcurves.Lateralcapacity,ductilityandenergydissipationcapacityofsinglepilesunderseismicloadwereevaluatedindetail.Thelateralcapacitiesandtheenergydissipationcapacityofpilesindensesandweremuchhigherthaninloosesand.Whenembeddedinloosesand,themaximumlateralloadandthemaximumlateraldisplacementofpilesincreasedase/dincreased.Onthecontrary,whenembeddedindensesand,themaximumlateralloadofpilesdecreasedase/dincreased.Pileswithahigherloadeccentricityratioexperiencedhigherenergydissipationcapacitythanpileswithe/dof0inbothdenseandloosesand.Atagivenlevelofdisplacement,pileswithcircularcrosssectionsprovidedthebestenergydissipationcapacityinbothlooseanddensesand.

简介：Shakingtabletestsofa1:10scalearchmodelperformedtoinvestigatetheseismicbehaviorandresistanceofconcretefilledsteeltubular(CFT)archstructuresaredescribedinthispaper.TheEl-CentrorecordandShanghaiartificialwavewereadoptedastheinputexcitation.Theentiretestprocesscanbedividedintothreestagesdependingonthelateralbraceconfigurations,i.e.,fully(five)braced,twobracesremoved,andallbracesremoved.Atotalof46tests,startingfromtheelasticstatetofailurecondition,havebeenconducted.Thenaturalvibrationfrequencies,responsesofacceleration,displacementandstrainweremeasured.Fromthetestresults,itisdemonstratedthattheCFTarchstructuresarecapableofresistingseveregroundmotionsandthatCFTarchesofferacrediblealternativetoreinforcedconcretearches,especiallyinregionsofhighseismicintensity.

简介：一个有力的数字模型的发展长有模仿具体材料的破裂行为是在地震工程的主导的研究区域之一。一个可靠模型应该能足够地代表裂缝的不连续的特征并且在复杂装载条件下面模仿各种各样的失败行为。在这篇论文，数字明确的表达，它合并一个复杂僵硬塑料的接口联合弄软的结合的组成的模型，接触，磨擦并且砍膨胀进XFEM，被建议描述具体材料的各种各样的裂缝行为。为精确地在断绝的双方上装配贡献到弱形式的一个有效数字集成计划被介绍。建议方法的有效性被模仿几著名试验性的测试估计了。数字方法罐头成功地捕获裂缝路径并且精确地预言具体结构的破裂行为，这被结束。混合模式破裂行为上的mode-II参数的影响进一步被调查更好决定这些参数。

简介：TiO2filmswereformedonmetallictitaniumsubstratesbytheanodicoxidationmethodinH2SO4solutionunderthe80VD.C..PhasecomponentandmicrostructurewerecharacterizedbyX-raydiffraction(XRD)andscanningelectronmicroscopy(SEM).Watercontactanglesontitaniumoxidefilmsurfaceweremeasuredunderbothdarkandsunlightilluminationconditions.Corrosiontestswerecarriedoutinseawaterunderdifferentilluminationconditionsbyelectrochemistryimpedancespectrum(EIS)andpolarizationcurves.TheresultshowedthattheTiO2filmpreparedbytheanodicoxidationmethodwasanatasewithauniformstructureandwithoutobviousporesorcracksonitssurface.Theaveragewatercontactangleofthefilmwas116.4?indark,incontrasttoanangleof42.7?undertheUVilluminationfor2hours,whichdemonstratesgoodhydrophobicproperty.Theanti-corrosionbehavioroftheTiO2filmwasdecliningwiththeextendedimmersiontime.Underdarkconditions,however,thehydrophobicTiO2filmretardedthewaterinfiltratingintothesubstrate.Theimpedancechangedslowlyandthecorrosioncurrentdensitywas2ordersofmagnitudelowerthanthatwiththefilmilluminatedbysunlight.AllofthosementionedaboveindicatethattheTiO2filmpossessesmuchbetterperformanceunderdarkcondition,anditcanbeappliedasanengineeringmaterialunderdarkseawaterenvironment.

简介：

简介：Inhighseismiczoneregions,slenderreinforcedconcretestructuralwallsarecommonlyusedinhigh-risebuildingsasamainlateralloadresistingelement.Thesewallsareveryeffectiveinlimitingthelateraldriftofthebuildingduetotheirlargein-planestiffness.However,thepresenceoffloorslabsinfluencesthebehavioroftheshearwall.Also,thecurrentdesignrequirementsdonotaccountforthepresenceoffloorslabs.Tounderstandthebehaviorofwall-slabjunctionsandaddresstheshortcomingsofthecurrentdesignrequirements,theinfluenceoftwoparameters,namely(a)aspectratioand(b)longitudinalreinforcementratioonthebehaviorisstudiednumerically.Itisobservedthatthepresenceoffloorslabsatdifferentlevelstendstopartitionthewallintosquatwallpanelsbetweentwoconsecutivefloors.Thewall-slabjunctionsshowlargestressconcentrationsarisingfromthestrutactioninthesquatpanels.Itisalsoobservedthatthefloorslabscangetsignificantlydamagednearthewall-slabjunctionforlowerverticalreinforcementratiosinthewall.Thus,thecurrentcodeprescribedminimumreinforcementinshearwallsisnotsufficientandneedstoberevisitedatforimprovedperformance.

简介：The2018PaluMW7.5earthquakeandtsunamiattractedgeophysicists'attentionforitsstrikeslipfocalmechanismandmagnitude.Weinspectedthedetailsofthisdisasteranddiscusseditsparticularityandpossiblecausations.Thesubmarinelandslideandspecialterrainconditionscouldhavecontributedtotheunusualsizeofthetsunami.Theearlywarningsystemandthepostdisasterresponseisalsoreviewed.Efficientsocialwarningsandbroadcastsystemsalongwithgoodmaintenanceisessential.Wealsofoundthatenhancingpublicsscientificliteracyisthemostimportantwaytoreducedisasterdamageandcasualties.Moreover,socialconditionsandrebuildingdifficultiesposttsunamiarerelatedasreferenceresourcesforfuturedisastermanagementstrategies.

简介：Metalgrainsinstonymeteoritesarerelativelymovableduringthermalnetamorphism(Wood,1967;XieandWang,1979;Xie,1986).InviewofthefactthattheJilinmeteoriteisthelargestintheworldknownuptonow,itsmainbodyweighing1770kganditstotalvolumeamountingto117×93×84cm^3,ade-tailedinvestigationintosuchahugemeteoritebodywouldundoubtedlyprovideuswithalotofcluesandinformationvaluableinthestudyofthebehaviorofFe-Nimetalduringthermalmetamorphismofmeteorites.OurrecentinvestigationhasrevealedthatduringthermalmetamorphismoftheJilinchondirtefineFe-Nimetalparticlesmigratedeasilybydiffusioninsolidstate,andsubsequentlyaggregatedintometalnodulesabout5-10mminlength,andthelargestnodulewefoundis30mminsize(Photo1).Inthispaperwepresentsomenewresultsofourstudyconcerningthemigra-tionandconcentrationofFe-NimetalintheJilinchondriteonthebasisofop-tical,SEMobservationsandhigh-temperature-highpressureaswellasshockloadingexperiments.

简介：Thisstudydescribestheseismicperformanceofanexistingfivestoreyreinforcedconcretebuildingwhichrepresentsthetypicalpropertiesoflow-risenon-ductilebuildingsinTurkey.Theeffectivenessofshearwallsandthesteelbracingsinretrofittingthebuildingwasexaminedthroughnonlinearstaticanddynamicanalyses.Byusingthenonlinearstaticanalysis,retrofittedbuildingsseismicperformancesunderlateralseismicloadwerecomparedwitheachother.Moreover,theperformancepointsandresponselevelsoftheexistingandretrofittingcasesweredeterminedbywayofthecapacity-spectrummethoddescribedinATC-40(1996).Forthenonlineardynamicanalysistherecordswereselectedtorepresentwiderangesofdurationandfrequencycontent.Consideringthechangeinthestiffnessandtheenergydissipationcapacities,theperformanceoftheexistingandretrofittedbuildingswereevaluatedintermsofstorydriftsanddamagestates.Itwasfoundthateachearthquakerecordexhibiteditsownpeculiarities,dictatedbyfrequencycontent,duration,sequenceofpeaksandtheiramplitude.Theseismicperformanceofretrofittedbuildingsresultedinlowerdisplacementsandhigherenergydissipationcapacitydependingmainlyonthepropertiesofthegroundmotionsandtheretrofittingstrategies.Moreover,severestructuraldamage(irreparableorcollapse)wasobservedfortheexistingbuilding.However,buildingswithretrofitalternativesexhibitedlowerdamagelevelschangingfromnodamagetoirreparabledamagestates.

简介：Ｑｕａｎｔｉｔａｔｉｖｅｓｔｕｄｙｏｎｃｈａｒａｃｔｅｒｉｓｔｉｃｐａｒａｍｅｔｅｒｓｏｆａｃｏｕｓｔｉｃｂｅｈａｖｉｏｒｈａｂｉｔｓｉｎｂｕｄｇｅｒｉｇａｒｓ（Ｍｅｌｏｐｓｉｔｔａｃｕｓｕｎｄｕｌａｆｕｓ）Ｊｉｎ－ＣｈａｎｇＪＩＡＮＧ（蒋锦昌）；Ｈ...

简介：垫子是在木排和地面之间的小粒的材料的层。在垫子和木排之间的接口的shear行为可以影响上层建筑的地震表演。为了确定，这影响，水平砍在在monotonic并且周期的装载下面的不同垫子材料和具体木排之间的接口上的测试被执行。垂直压力Pv,材料类型和垫子厚度hc作为变量被拿。结论包括：1)在装载的monotonic下面，Pv是最重要的因素；shear抵抗Phmax作为Pv增加，而是抵抗n有一个相反的趋势；2)因为材料在这研究使用了，n从0.40～0.70变化，接口磨擦角度s从20变化

简介：

简介：Thispaperdescribesaseriesofexperimentalinvestigationsonseventeenspecimensofsteelreinforcedconcretespecialshaped(SRCSS)columnsunderlowcyclicreversedloadingusingparallelcrossheadequipment.NineT-shapedSRCcolumns,fourL-shapedSRCcolumnsandfour+-shapedSRCcolumnsweretestedtoexaminetheeffectsofshapesteelconfiguration,loadingangle,axialcompressiveratioandshear-spanratioonthebehavior(strength,stiffness,energydissipation,ductility,etc.)ofSRCSScolumnspecimens.Thefailuremodesandhystereticperformanceofallthespecimenswereobtainedinthetests.Testresultsdemonstratethattheshear-spanratioisthemainparameteraffectingthefailuremodesofSRCSScolumns.Thespecimenswithsmallshear-spanratioarepronetoshearfailure,andtheprimaryfailureplanesinSRCSScolumnsareparalleltotheloadingdirection.Asaresult,thereisasymmetrybetweenpositiveandnegativeloadingdirectionsinthehystereticcurvesoftheSRCSScolumns.Themajorityofdisplacementductilitycoefficientsforallthespecimensareover3.0,sothattheSRCSScolumnsdemonstrateabetterdeformationcapacity.Inaddition,theequivalentviscousdampingcoefficientsofallthespecimensaregreaterthan0.2,indicatingthattheseismicbehaviorofSRCSScolumnsisadequate.Finally,thesuperpositiontheorywasusedtocalculatethelimitsofaxialcompressiveratioforthespecimens,anditisfoundthatthetestaxialcompressiveratioisclosetoorsmallerthanthecalculatedaxialcompressiveratiolimit.