involving网易yeah
网易yeah 时间:2021-02-16 阅读:()
APFIS2017-6thAsia-PacificConferenceonFRPinStructuresSingapore,19-21stJuly20171HaiFang,HuiyuanShi,WeiqingLiu,YujunQi,andRuiliHuoENHANCEMENTEFFECTANALYSISOFLATTICE-WEBSTOGFRP-WOODSANDWICHBEAMSINFLATWISEANDSIDEWISEBENDINGHaiFang1*,HuiyuanShi2,WeiqingLiu3,YujunQi4,RuiliHuo51Correspondingauthor,CollegeofCivilEngineering,NanjingTechUniversity,Nanjing,ChinaEmail:fanghainjut@njtech.
edu.
cn,WebPage:http://cce.
njtech.
edu.
cn/view.
aspid=527&class=2212SchoolofCivilEngineering,SoutheastUniversity,Nanjing,ChinaEmail:hyshiseu@yeah.
net3AdvancedEngineeringCompositesResearchCenter,NanjingTechUniversity,Nanjing,ChinaEmail:wqliu@njtech.
edu.
cn,WebPage:http://cce.
njtech.
edu.
cn/view.
aspid=485&class=2404CollegeofCivilEngineering,NanjingTechUniversity,Nanjing,ChinaEmail:qiyujun11@163.
com,WebPage:http://cce.
njtech.
edu.
cn/view.
aspid=1385&class=2215CollegeofCivilEngineering,NanjingTechUniversity,Nanjing,ChinaEmail:ruilihuo@njtech.
edu.
cnKeywords:GFRP-woodsandwichbeams,lattice-webreinforced,flexural,flatwise,sidewiseAbstractThispaperinvestigatestheflexuralbehaviorinflatwiseandsidewisepositionsofnovelgenerationcompositesandwichbeamswithPaulowniaandsouthernpinewoodcoreandglass-fiberreinforcedpolymer(GFRP)facesheetandlattice-webs.
Avacuumassistedresininfusionprocess(VARI)wasemployedtoformsandwichbeamswithdifferentnumbersofwebs.
Twocontrolwoodenbeamsandeighteenlattice-webreinforcedsandwichbeamsweresubjectedtofour-pointbendingteststodeterminetheirstiffness,capacity,andfailuremechanismsintheflatwiseandsidewisepositions.
Theexperimentalresultsrevealedthatthecompositesandwichbeamsfailedinflatwisebendingtestsunderlowerloadbutproducedagreaterdeflectioncomparedtothebeamsinsidewisebendingtests.
Withtheincreaseinthenumberoflattice-webs,ductilitywasfoundtoincreaseinflatwisepositionswhiledecreasinginsidewisepositions.
Analyticalformulasforcalculatingthebendingstiffness,capacity,andductilityoftheGFRP-woodsandwichbeamswereprovided,andtheanalysisresultsformechanicalperformanceshowedgoodagreementwiththeexperimentalresults.
1.
IntroductionComparedtotraditionalconstructionmaterials,themainbenefitsofGFRPcompositematerialinstructuralcomponentsareitshighstrength,excellentcorrosionresistance,easeofhandingandapplication,andflexibilityofdesign[1].
Inthispaperwepresentanewgenerationofcompositesandwichbeamsintendedforuseasloading-bearingcomponents.
Thecompositesandwichisintegrallyformedinthemoldbyavacuum-assistedresininfusionprocessinvolvingcompositeface-skins,webs,andcorematerials,asshowninFigure1.
Onenovelfeatureisthebundlingofthecorematerials,mainlycharacterizedbyhighstrength,intoinbothwebs.
Thesandwichbeams,thatclearlyenhancetheantistrippingandcooperativeperformancebetweensurfacelayerandcore,areconstructedbycloselywrappingwoodcorematerialstogetherusinglattice-websandface-skinsthatcangivefullplaytothepropertiesofthebendingandshearcapacityofthesandwichbeams.
Whenthesurfacelayerofthecompositesandwichbeamisundernormalload,themainfunctionofthewoodcoreistoimproveshapingandbearingandtoprovideelasticsupportsforthesandwichbeams.
Thecompositesandwichbeamavoidstheoccurrenceoflocalbucklinganddebonding,becausethecorematerialimprovesthedistributionofsectionstress,APFIS2017-6thAsia-PacificConferenceonFRPinStructuresSingapore,19-21stJuly20172HaiFang,HuiyuanShi,WeiqingLiu,YujunQi,andRuiliHuoeffectivelyreducingthestressconcentrationattheintersectionofthesurfacelayerandlattice-webs,significantlydelayingsplittingfailure.
Meanwhile,theGFRPlattice-webscaneffectivelyincreasethecapacityofshear,compression,andstripping,bothintheflatwise(horizontal)orinthesidewise(vertical)position.
Inthispaper,theultimatefailuremechanisms,initialbendingstiffness,load-deflectionbehaviorandstress-strainbehaviorofGFRP-woodsandwichbeamsunderfour-pointstaticbendingintheflatwiseandsidewisepositionsarereportedanddiscussed.
Thetheoreticaloutcomesforthestiffnessandstrengthofthecompositesandwichbeamsarealsopredictedandcomparedwiththeexperimentalresults.
(a)(b)(c)Figure1.
Lattice-webreinforcedcompositesandwichbeams(a)flatwise,(b)sidewise,and(c)cross-sectionalviewofrealobject.
2.
ExperimentalProgram2.
1.
TestSpecimensandMaterialsThestructuralsandwichbeamstestedinthisstudywereemployedusingGFRPskinsandlattice-webscomposedofbi-axial[0/90]glassfiberlaminates(800g/m2)andHS-2101-G100unsaturatedpolyesterresintowrapthecorematerialstogether.
High-classPaulowniaorsouthernpinewood,weighing280kg/m3and500kg/m3respectively,werefilledascorematerialsinthesespecimens.
Theoveralldensityofthecompositesandwichbeamswasmuchlessthanthatofconcreteandsteel,withdensitiesof2400kg/m3and7850kg/m3respectively.
Table1summariestheultimatestrengthandYoung'smodulusoftheGFRPface-skins,lattice-webs,andcorematerials.
Table1.
Effectivemechanicalpropertiesoftheglassfiberskinsandcorematerials.
PropertiesSkinsandwebsPaulowniawoodSouthernpinewoodCompressionUltimatestrength(MPa)223.
7426.
5332.
76Young'smodulus(GPa)16.
011.
863.
57TensionUltimatestrength(MPa)305.
00——Young'smodulus(GPa)20.
95——ShearUltimatestrength(MPa)16.
273.
346.
55Young'smodulus(GPa)7.
680.
420.
68Twentysandwichbeamswithidenticaldimensions(1400mm*120mm*120mm),including2woodenbeams,2compositesandwichbeamswithoutlattice-webs,and16sandwichbeamswithlattice-webs,werefabricatedandmanufacturedintheAdvancedCompositeStructuresResearchInstituteatNanjingTechUniversity.
DetailsofeachspecimenaresummarizedinTable2.
Horizontallattice-websVerticallattice-websAPFIS2017-6thAsia-PacificConferenceonFRPinStructuresSingapore,19-21stJuly20173HaiFang,HuiyuanShi,WeiqingLiu,YujunQi,andRuiliHuoTable2.
Descriptionofspecimens.
SpecimensSizeofspecimenSizeofcoreOrientationoftestingl(mm)B(mm)H(mm)b(mm)h(mm)PA/SP-CON-F/S1400120120120120FlatwiseandsidewisePA/SP-0-F/S1400120120110110FlatwiseandsidewisePA/SP-1-F140012012011053.
0FlatwisePA/SP-2-F140012012011034.
0FlatwisePA/SP-3-F140012012011024.
5FlatwisePA/SP-4-F140012012011018.
8FlatwisePA/SP-1-S140012012053.
0110SidewisePA/SP-2-S140012012034.
0110SidewisePA/SP-3-S140012012024.
5110SidewisePA/SP-4-S140012012018.
8110Sidewise2.
2.
TestSet-upandInstrumentationThespecimenswereloadedunderstaticfour-pointbendinginaccordancewiththeASTMC393standard[2]byauniversaltestingmachine.
Theloadingexperimentalsetupemployedinthetestswassimplysupportedandthenetspanwas1200mmbetweenthetworollersupports.
Averticalmonotonicloadingwassetbya300kNcapacityhydraulicjack,whichwasequallysplituptotwocentralpointsonthespecimensbyasteeltransferbeamandmovedataloadingrateof2mm/min,asshowninFigure2.
Duringtesting,straincollectionwasperformedbyaDH3816staticstraintestsystem.
TheverticaldisplacementwasmeasuredbyaLVDT(linearvariabledeflectiontransducer)arrangedatthebottomofmid-spanandthetopofsupport.
Twolongitudinalstraingaugestoobservetherelationoftheloadandthestrainoftheface-skinwereattachedtothetopandbottomface-skinsofthemid-span.
Figure2.
Experimentalsetupofflexuralbehaviorofthebeam:(a)pictureofflexuraltestsetup,(b)schematicplot,and(c)straingaugearrangement.
3.
ExperimentalResultsandDiscussionControlspecimensPA-CON-F/SandSP-CON-F/Sfailedinabrittlemanner,asshowninFigure3a.
Theappearanceofsheartensilecrackswasfirstobserved.
Owingtothemaximumshearstrainofthewoodexceedsitscrushingstrain,thesecracks,thatsuddenlyproducedaloudnoise,rapidlyextendedupwardandcausedimmediatefailurewiththeincreaseofslowloadandquickdeflection.
InthecompositesandwichspecimensPA-0-F/SandSP-0-F/S,withoutlatticewebs,brittlefailuredidnotoccurbecausethefibercompositeexternalskinsonthetensilefaceofthespecimensbridgedthecrackedcorecomponentstogethertopreventfailure.
Whenthemaximumcompressivestrainoftheexternalsurfaceexceededitscompressivestrain,toplocalindentationoccurredaswellascompressivecracksonthelateralface-skin,asshowninFigure3b.
Specimenswith1,2,3,and4websintheAPFIS2017-6thAsia-PacificConferenceonFRPinStructuresSingapore,19-21stJuly20174HaiFang,HuiyuanShi,WeiqingLiu,YujunQi,andRuiliHuoflatwisepositionsmainlyfailedbycrushingofthefibercompositeskinsattheloadingpointfollowedbytheoccurrenceofsplittingofthebottomglassfibercausedbyalargedeformationatthebottomofthebeam,asshowninFigure3c.
Compressivewrinklingwasobservedinthesidewisepositions,asshowninFigure3d,andcontinuousapplicationofloadcausedcrackspreadingextendingfromtheuppermosttotheundersection,followedbycompressivefailure.
(a)(b)(c)(d)Figure3.
FailuremodesofGFRP-woodsandwichbeams.
Fromtheexperimentaldataitcanbeseenthattheload-deflectionbehaviorofthespecimenschangesfromlineartononlinearwiththeincreaseinappliedload.
AsshowninFigure4aand4b,whenthecoreisPaulownia,theultimatebendingstrengthofspecimensPA-(1~4)-SisbasicallygreaterthanthatofspecimensPA-(1~4)-F,amongwhichPA-3isthemostobvious.
ThesetrendsinFigure4cand4dcanalsobefoundwithsouthernpinecore.
Meanwhile,theultimatebearingcapacityofthebeamswithsouthernpinewoodisslighterhigherthanthatofbeamswithPaulownia.
Itcanbeconcludedthattheuseofverticalwebsandtheapplicationofhigh-strengthcorematerialwillobtaingreaterbendingstiffnessofthebeam.
(a)(b)(c)(d)Figure4.
Load-deflectioncurvesforsandwichbeam.
4.
ConclusionsInvestigationoftheflexuralbehaviorofinnovativecompositesandwichbeamsreinforcedbylattice-websunderfour-pointstaticbendingtestintheflatwiseandsidewisepositionswasundertakenexperimentallyinthispaper.
WiththisstudyoftheseGFRPsandwichbeams,onegoalistomaximallyincreasethevalueofthesespecimens;theothergoalistoseekastructuretosubstitutefortraditionalbeamsthatwereeasilysubjecttobrittlefailureanddelamination.
Itwasfoundthat,toimprovethecapacityofstiffness,strength,andmonolithicstability,settingupappropriatelaminationandorientationofthelatticewebsforthesandwichbeamsisnecessary.
TheapplicationoffiberinsertionswasfoundtobeviableinthereinforcementandrecoveryofGFRP-woodbeams.
Thistechniqueisnotonlyeasybutalsoconfersgreaterstrengthandstiffnessofreinforcedstructuralelements.
Italsorendersthesystemmorereliable,reducingthepossibilityoftensilefailurecausedbydefects.
APFIS2017-6thAsia-PacificConferenceonFRPinStructuresSingapore,19-21stJuly20175HaiFang,HuiyuanShi,WeiqingLiu,YujunQi,andRuiliHuoAcknowledgmentsTheresearchdescribedherewassupportedbytheNationalNaturalScienceFoundationofChina(GrantNo.
51578285)andfundedbythePriorityAcademicProgramDevelopmentofJiangsuHigherEducationInstitutionsPAPD(GrantNo.
CE02-1-11).
References[1]ZamanA,GutubSA,WafaMA.
AreviewonFRPcompositesapplicationsanddurabilityconcernsintheconstructionsector.
JReinfPlastCompos,2013,32(24):1966-1988.
[2]ASTMC393/C393M-16,Standardtestmethodforcoreshearpropertiesofsandwichconstructionsbybeamflexure,ASTMInternational,WestConshohocken,PA,2016.
edu.
cn,WebPage:http://cce.
njtech.
edu.
cn/view.
aspid=527&class=2212SchoolofCivilEngineering,SoutheastUniversity,Nanjing,ChinaEmail:hyshiseu@yeah.
net3AdvancedEngineeringCompositesResearchCenter,NanjingTechUniversity,Nanjing,ChinaEmail:wqliu@njtech.
edu.
cn,WebPage:http://cce.
njtech.
edu.
cn/view.
aspid=485&class=2404CollegeofCivilEngineering,NanjingTechUniversity,Nanjing,ChinaEmail:qiyujun11@163.
com,WebPage:http://cce.
njtech.
edu.
cn/view.
aspid=1385&class=2215CollegeofCivilEngineering,NanjingTechUniversity,Nanjing,ChinaEmail:ruilihuo@njtech.
edu.
cnKeywords:GFRP-woodsandwichbeams,lattice-webreinforced,flexural,flatwise,sidewiseAbstractThispaperinvestigatestheflexuralbehaviorinflatwiseandsidewisepositionsofnovelgenerationcompositesandwichbeamswithPaulowniaandsouthernpinewoodcoreandglass-fiberreinforcedpolymer(GFRP)facesheetandlattice-webs.
Avacuumassistedresininfusionprocess(VARI)wasemployedtoformsandwichbeamswithdifferentnumbersofwebs.
Twocontrolwoodenbeamsandeighteenlattice-webreinforcedsandwichbeamsweresubjectedtofour-pointbendingteststodeterminetheirstiffness,capacity,andfailuremechanismsintheflatwiseandsidewisepositions.
Theexperimentalresultsrevealedthatthecompositesandwichbeamsfailedinflatwisebendingtestsunderlowerloadbutproducedagreaterdeflectioncomparedtothebeamsinsidewisebendingtests.
Withtheincreaseinthenumberoflattice-webs,ductilitywasfoundtoincreaseinflatwisepositionswhiledecreasinginsidewisepositions.
Analyticalformulasforcalculatingthebendingstiffness,capacity,andductilityoftheGFRP-woodsandwichbeamswereprovided,andtheanalysisresultsformechanicalperformanceshowedgoodagreementwiththeexperimentalresults.
1.
IntroductionComparedtotraditionalconstructionmaterials,themainbenefitsofGFRPcompositematerialinstructuralcomponentsareitshighstrength,excellentcorrosionresistance,easeofhandingandapplication,andflexibilityofdesign[1].
Inthispaperwepresentanewgenerationofcompositesandwichbeamsintendedforuseasloading-bearingcomponents.
Thecompositesandwichisintegrallyformedinthemoldbyavacuum-assistedresininfusionprocessinvolvingcompositeface-skins,webs,andcorematerials,asshowninFigure1.
Onenovelfeatureisthebundlingofthecorematerials,mainlycharacterizedbyhighstrength,intoinbothwebs.
Thesandwichbeams,thatclearlyenhancetheantistrippingandcooperativeperformancebetweensurfacelayerandcore,areconstructedbycloselywrappingwoodcorematerialstogetherusinglattice-websandface-skinsthatcangivefullplaytothepropertiesofthebendingandshearcapacityofthesandwichbeams.
Whenthesurfacelayerofthecompositesandwichbeamisundernormalload,themainfunctionofthewoodcoreistoimproveshapingandbearingandtoprovideelasticsupportsforthesandwichbeams.
Thecompositesandwichbeamavoidstheoccurrenceoflocalbucklinganddebonding,becausethecorematerialimprovesthedistributionofsectionstress,APFIS2017-6thAsia-PacificConferenceonFRPinStructuresSingapore,19-21stJuly20172HaiFang,HuiyuanShi,WeiqingLiu,YujunQi,andRuiliHuoeffectivelyreducingthestressconcentrationattheintersectionofthesurfacelayerandlattice-webs,significantlydelayingsplittingfailure.
Meanwhile,theGFRPlattice-webscaneffectivelyincreasethecapacityofshear,compression,andstripping,bothintheflatwise(horizontal)orinthesidewise(vertical)position.
Inthispaper,theultimatefailuremechanisms,initialbendingstiffness,load-deflectionbehaviorandstress-strainbehaviorofGFRP-woodsandwichbeamsunderfour-pointstaticbendingintheflatwiseandsidewisepositionsarereportedanddiscussed.
Thetheoreticaloutcomesforthestiffnessandstrengthofthecompositesandwichbeamsarealsopredictedandcomparedwiththeexperimentalresults.
(a)(b)(c)Figure1.
Lattice-webreinforcedcompositesandwichbeams(a)flatwise,(b)sidewise,and(c)cross-sectionalviewofrealobject.
2.
ExperimentalProgram2.
1.
TestSpecimensandMaterialsThestructuralsandwichbeamstestedinthisstudywereemployedusingGFRPskinsandlattice-webscomposedofbi-axial[0/90]glassfiberlaminates(800g/m2)andHS-2101-G100unsaturatedpolyesterresintowrapthecorematerialstogether.
High-classPaulowniaorsouthernpinewood,weighing280kg/m3and500kg/m3respectively,werefilledascorematerialsinthesespecimens.
Theoveralldensityofthecompositesandwichbeamswasmuchlessthanthatofconcreteandsteel,withdensitiesof2400kg/m3and7850kg/m3respectively.
Table1summariestheultimatestrengthandYoung'smodulusoftheGFRPface-skins,lattice-webs,andcorematerials.
Table1.
Effectivemechanicalpropertiesoftheglassfiberskinsandcorematerials.
PropertiesSkinsandwebsPaulowniawoodSouthernpinewoodCompressionUltimatestrength(MPa)223.
7426.
5332.
76Young'smodulus(GPa)16.
011.
863.
57TensionUltimatestrength(MPa)305.
00——Young'smodulus(GPa)20.
95——ShearUltimatestrength(MPa)16.
273.
346.
55Young'smodulus(GPa)7.
680.
420.
68Twentysandwichbeamswithidenticaldimensions(1400mm*120mm*120mm),including2woodenbeams,2compositesandwichbeamswithoutlattice-webs,and16sandwichbeamswithlattice-webs,werefabricatedandmanufacturedintheAdvancedCompositeStructuresResearchInstituteatNanjingTechUniversity.
DetailsofeachspecimenaresummarizedinTable2.
Horizontallattice-websVerticallattice-websAPFIS2017-6thAsia-PacificConferenceonFRPinStructuresSingapore,19-21stJuly20173HaiFang,HuiyuanShi,WeiqingLiu,YujunQi,andRuiliHuoTable2.
Descriptionofspecimens.
SpecimensSizeofspecimenSizeofcoreOrientationoftestingl(mm)B(mm)H(mm)b(mm)h(mm)PA/SP-CON-F/S1400120120120120FlatwiseandsidewisePA/SP-0-F/S1400120120110110FlatwiseandsidewisePA/SP-1-F140012012011053.
0FlatwisePA/SP-2-F140012012011034.
0FlatwisePA/SP-3-F140012012011024.
5FlatwisePA/SP-4-F140012012011018.
8FlatwisePA/SP-1-S140012012053.
0110SidewisePA/SP-2-S140012012034.
0110SidewisePA/SP-3-S140012012024.
5110SidewisePA/SP-4-S140012012018.
8110Sidewise2.
2.
TestSet-upandInstrumentationThespecimenswereloadedunderstaticfour-pointbendinginaccordancewiththeASTMC393standard[2]byauniversaltestingmachine.
Theloadingexperimentalsetupemployedinthetestswassimplysupportedandthenetspanwas1200mmbetweenthetworollersupports.
Averticalmonotonicloadingwassetbya300kNcapacityhydraulicjack,whichwasequallysplituptotwocentralpointsonthespecimensbyasteeltransferbeamandmovedataloadingrateof2mm/min,asshowninFigure2.
Duringtesting,straincollectionwasperformedbyaDH3816staticstraintestsystem.
TheverticaldisplacementwasmeasuredbyaLVDT(linearvariabledeflectiontransducer)arrangedatthebottomofmid-spanandthetopofsupport.
Twolongitudinalstraingaugestoobservetherelationoftheloadandthestrainoftheface-skinwereattachedtothetopandbottomface-skinsofthemid-span.
Figure2.
Experimentalsetupofflexuralbehaviorofthebeam:(a)pictureofflexuraltestsetup,(b)schematicplot,and(c)straingaugearrangement.
3.
ExperimentalResultsandDiscussionControlspecimensPA-CON-F/SandSP-CON-F/Sfailedinabrittlemanner,asshowninFigure3a.
Theappearanceofsheartensilecrackswasfirstobserved.
Owingtothemaximumshearstrainofthewoodexceedsitscrushingstrain,thesecracks,thatsuddenlyproducedaloudnoise,rapidlyextendedupwardandcausedimmediatefailurewiththeincreaseofslowloadandquickdeflection.
InthecompositesandwichspecimensPA-0-F/SandSP-0-F/S,withoutlatticewebs,brittlefailuredidnotoccurbecausethefibercompositeexternalskinsonthetensilefaceofthespecimensbridgedthecrackedcorecomponentstogethertopreventfailure.
Whenthemaximumcompressivestrainoftheexternalsurfaceexceededitscompressivestrain,toplocalindentationoccurredaswellascompressivecracksonthelateralface-skin,asshowninFigure3b.
Specimenswith1,2,3,and4websintheAPFIS2017-6thAsia-PacificConferenceonFRPinStructuresSingapore,19-21stJuly20174HaiFang,HuiyuanShi,WeiqingLiu,YujunQi,andRuiliHuoflatwisepositionsmainlyfailedbycrushingofthefibercompositeskinsattheloadingpointfollowedbytheoccurrenceofsplittingofthebottomglassfibercausedbyalargedeformationatthebottomofthebeam,asshowninFigure3c.
Compressivewrinklingwasobservedinthesidewisepositions,asshowninFigure3d,andcontinuousapplicationofloadcausedcrackspreadingextendingfromtheuppermosttotheundersection,followedbycompressivefailure.
(a)(b)(c)(d)Figure3.
FailuremodesofGFRP-woodsandwichbeams.
Fromtheexperimentaldataitcanbeseenthattheload-deflectionbehaviorofthespecimenschangesfromlineartononlinearwiththeincreaseinappliedload.
AsshowninFigure4aand4b,whenthecoreisPaulownia,theultimatebendingstrengthofspecimensPA-(1~4)-SisbasicallygreaterthanthatofspecimensPA-(1~4)-F,amongwhichPA-3isthemostobvious.
ThesetrendsinFigure4cand4dcanalsobefoundwithsouthernpinecore.
Meanwhile,theultimatebearingcapacityofthebeamswithsouthernpinewoodisslighterhigherthanthatofbeamswithPaulownia.
Itcanbeconcludedthattheuseofverticalwebsandtheapplicationofhigh-strengthcorematerialwillobtaingreaterbendingstiffnessofthebeam.
(a)(b)(c)(d)Figure4.
Load-deflectioncurvesforsandwichbeam.
4.
ConclusionsInvestigationoftheflexuralbehaviorofinnovativecompositesandwichbeamsreinforcedbylattice-websunderfour-pointstaticbendingtestintheflatwiseandsidewisepositionswasundertakenexperimentallyinthispaper.
WiththisstudyoftheseGFRPsandwichbeams,onegoalistomaximallyincreasethevalueofthesespecimens;theothergoalistoseekastructuretosubstitutefortraditionalbeamsthatwereeasilysubjecttobrittlefailureanddelamination.
Itwasfoundthat,toimprovethecapacityofstiffness,strength,andmonolithicstability,settingupappropriatelaminationandorientationofthelatticewebsforthesandwichbeamsisnecessary.
TheapplicationoffiberinsertionswasfoundtobeviableinthereinforcementandrecoveryofGFRP-woodbeams.
Thistechniqueisnotonlyeasybutalsoconfersgreaterstrengthandstiffnessofreinforcedstructuralelements.
Italsorendersthesystemmorereliable,reducingthepossibilityoftensilefailurecausedbydefects.
APFIS2017-6thAsia-PacificConferenceonFRPinStructuresSingapore,19-21stJuly20175HaiFang,HuiyuanShi,WeiqingLiu,YujunQi,andRuiliHuoAcknowledgmentsTheresearchdescribedherewassupportedbytheNationalNaturalScienceFoundationofChina(GrantNo.
51578285)andfundedbythePriorityAcademicProgramDevelopmentofJiangsuHigherEducationInstitutionsPAPD(GrantNo.
CE02-1-11).
References[1]ZamanA,GutubSA,WafaMA.
AreviewonFRPcompositesapplicationsanddurabilityconcernsintheconstructionsector.
JReinfPlastCompos,2013,32(24):1966-1988.
[2]ASTMC393/C393M-16,Standardtestmethodforcoreshearpropertiesofsandwichconstructionsbybeamflexure,ASTMInternational,WestConshohocken,PA,2016.
- involving网易yeah相关文档
- 网易网易hr管培生北京笔试试题
- 照片一篇完整的网易笔试题
- 扁豆网易yeah
- 0.21网易yeah
- 戏曲网易yeah
- 3.2网易yeah
台湾CN2云服务器 2核2G 5M 5IP 台湾物理服务器 E5x2 64G 20M 5IP
提速啦（www.tisula.com）是赣州王成璟网络科技有限公司旗下云服务器品牌，目前拥有在籍员工40人左右，社保在籍员工30人+，是正规的国内拥有IDC ICP ISP CDN 云牌照资质商家，2018-2021年连续4年获得CTG机房顶级金牌代理商荣誉 2021年赣州市于都县创业大赛三等奖，2020年于都电子商务示范企业，2021年于都县电子商务融合推广大使。资源优势介绍：Ceranetwo...
JUSTG提供俄罗斯和南非CN2 GIA主机年$49.99美元JUSTGgia南非cn2南非CN2justG
JUSTG，这个主机商第二个接触到，之前是有介绍到有提供俄罗斯CN2 GIA VPS主机活动的，商家成立时间不久看信息是2020年，公司隶属于一家叫AFRICA CLOUD LIMITED的公司，提供的产品为基于KVM架构VPS主机，数据中心在非洲（南非）、俄罗斯（莫斯科），国内访问双向CN2，线路质量不错。有很多服务商实际上都是国人背景的，有的用英文、繁体搭建的冒充老外，这个服务商不清楚是不是真...
ThomasHost(月付5美元)美国/法国/英国/加拿大KVM,支持Windows
ThomasHost域名注册自2012年，部落最早分享始于2016年，还算成立了有几年了，商家提供基于KVM架构的VPS，数据中心包括美国、法国、英国、加拿大和爱尔兰等6个地区机房，VPS主机套餐最低2GB内存起步，支持Windows或者Linux操作系统，1Gbps端口不限制流量。最近商家提供了一个5折优惠码，优惠后最低套餐月付5美元起。下面列出部分套餐配置信息。CPU：1core内存：2GB硬...
网易yeah为你推荐
-
戴尔智能数据管理yw372:Com帮个忙 这个视频源地址怎么找http://video.kuaiji.com/congye/diansuanhua/372/3097internalservererrorError 500--Internal Server Error 求教这个问题怎么解决？企业推广最常见的推广方式有哪些支付宝蜻蜓发布支付宝蜻蜓f4，可以让没有支付宝的人刷脸付款？字节跳动回应TikTok易主#北京字节跳动科技有限公司#小说审核有三面么？我面试了两轮就叫我回家等消息了 要是刷下来了也该告ldapserverLDAP3是什么加多宝和王老吉王老吉和加多宝是什么关系2828商机网2828商机网的信息准确吗，可信度高吗billboardchina中国有进美国BillBoard榜的人吗