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竹子方面论文范文参考文献,与gocheck文检测试题相关毕业论文

本论文是一篇竹子方面毕业论文,关于gocheck文检测试题相关本科毕业论文范文。免费优秀的关于竹子及工业工程及建筑材料方面论文范文资料,适合竹子论文写作的大学硕士及本科毕业论文开题报告范文和学术职称论文参考文献下载。

all-sizedscreens.Theeffectcanbestunning,andalsopracticalinpartsoftheworldwherebamboothrives.

Buttherearelimitationstobuildingwithbamboo.Thehardygrassisvulnerabletoinsects,andbuildingwithstalks—essentiallyhollowcylinders—limitstheshapeofindividualbuildingponents,aswellasthedurabilityofthebuildingitself.

MassachusettsInstituteofTechnology(MIT)scientists,alongwitharchitectsandwoodprocessorsfromEnglandandCanada,arelookingforwaystoturnbamboointoaconstructionmaterialmoreakintowoodposites,likeplywood.Theideaisthatastalk,orculm,canbeslicedintosmallerpieces,whichcanthenbebondedtogethertoformsturdyblocks—muchlikeconventionalwoodposites.Astructuralproductofthissortcouldbeusedtoconstructmoreresilientbuildings—particularlyinplaceslikeChina,IndiaandBrazil,wherebambooisabundant.

Suchbambooproductsarecurrentlybeingdevelopedbyseveralpanies.TheMITprojectintendstogainabetterunderstandingofthesematerials,sothatbamboocanbemoreeffectivelyusedstructurally.Tothatend,MITresearchershavenowanalyzedthemicrostructureofbambooandfoundthattheplantisstrongeranddenserthanNorthAmericansoftwoodslikepine,firandspruce,makingthegrassapromisingresourceforpositematerials.

Bamboogrowsextensivelyinregionswheretherearerapidlydevelopingeconomies,soit'sanalternativebuildingmaterialtoconcreteandsteel,"saysLornaGibson,theMatoulaS.SalapatasProfessorofMaterialsScienceandEngineeringatMIT."Youprobablywouldn'tmakeaskyscraperoutofbamboo,butcertainlysmallerstructureslikehousesandlow-risebuildings."

Gibsonandhercolleaguesanalyzedsectionsofbamboofromtheinsideout,measuringthestiffnessofeachsectionatthemicroscale.Asitturnsout,bambooisdensestnearitsouterwalls.Theresearchersusedtheirdatatodevelopamodelthatpredictsthestrengthofagivensectionofbamboo.

Themodelmayhelpwoodprocessorsdeterminehowtoassembleaparticularbambooproduct.AsGibsonexplainsit,onesectionofbamboomaybemoresuitableforagivenproductthananother:"Ifyouwantedabamboobeamthatbends,maybeyou'dwanttoputthedensermaterialatthetopandbottomandthelessdensebitstowardthemiddle,asthestressesinthebeamarelargeratthetopandbottomandsmallerinthemiddle.We'relookingathowwemightoptimizetheselectionofbamboomaterialsinthestructurethatyoumake."

GibsonandhercolleagueshavepublishedtheirresultsintheJournaloftheRoyalSociety:Interface.

Alookatbamboo,fromtheinsideout

Fortheirexperiments,theresearchersanalyzedspecimensofmoso,themainspeciesofbamboousedinChina.Likemosttypesofbamboo,mosogrowsashollow,cylindricalstalks,orculms,segmentedbynodesalongthelengthofastalk.Bamboocanreachheightsof20m—astallasasix-storybuilding—injustafewmonths.Thestalksthentakeanotherfewyearstomature—butstillmuchfasterthanapinetree'sstatelier,decades-longgrowth.

Oneoftheimpressivethingsishowfastbamboogrows,"Gibsonnotes."Ifyouplantedapineforestversusabambooforest,youwouldfindyoucangrowfarmorebamboo,andfaster."

Researchersusedelectronmicroscopytoobtainimagesofthebamboomicrostructureandcreateplete,microscalecross-sectionsoftheentireculmwallatdifferentheightsalongthestalk.

Theresultingimagesshoweddensitygradientsofvascularbundles—hollowvessels—thatcarryfluidupanddownthestalk,surroundedbysolidfibrouscells.Thedensityofthesebundlesincreasesradiallyoutward—agradientthatseemstogrowmorepronouncedathigherpositionsalongastalk.

Theresearcherscutsectionsofbamboofromtheinsideout,notingeachsample'sradialandlongitudinalpositionalongaculm,thengaugedthestiffnessandstrengthofthesamplesbyperformingbendingandpressiontests.Inparticular,theyperformednanoindentation,whichusesatinymechanicaltiptopushdownonasample,togainanunderstandingofbamboo'smaterialpropertiesatafinerscale.Fromtheresultsofthesemechanicaltests,Gibsonandhercolleaguesfoundthatingeneral,bambooisstifferandstrongerthanmostNorthAmericansoftwoodsmonlyusedinconstruction,andalsodenser.

Theresearchersthenusedthestiffnessanddensitydatatocreateamodelthataccuratelypredictsthemechanicalpropertiesofbambooasafunctionofpositioninthestalk.GibsonsayswoodprocessorsthatsheworkswithinCanadamayusethemodelasaguidetoassembledurablebambooblocksofvariousshapesandsizes.

Goingforward,theprocessors,inturn,willsendtheMITteampositesamplesofbambootocharacterize.Forexample,aproductmaybeprocessedtocontainbambooalongwithothermaterialstoreducethedensityoftheproductandmakeitresistanttoinsects.Suchpositematerials,Gibsonsays,willhavetobeunderstoodatthemicroscale.

Wewanttolookattheoriginalmechanicalpropertiesofthebambooculm,aswellashowprocessingaffectstheproduct,"Gibsonsays."Maybethere'sawaytominimizeanyeffects,andusebambooinamoreversatileway."

Source:MassachusettsInstituteofTechnology

建造竹子机构

竹构建筑在传统上是非常简单的:整个秸秆被用来创建网格状的大厦,或纺织成条以形成墙壁大小的屏风.其效果是令人惊叹的,并且在竹子蓬勃发展的世界各地也是非常实际的.

但是运用竹子来进行建造也是具有局限性的.耐寒的草容易招至昆虫,并且

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