Abstract :
Aniterativenumericalcomputationalalgorithmisdevelopedtodesignaplateorshellelementsubjectedtomembraneandflexuralforces,whichisbasedonequilibriumconsiderationsforthelimitedultimatestateofthereinforcementandcrackedconcrete.Equationsforcapacitiesoftopandbottomreinforcementsintwoorthogonaldirectionshavebeenderived.
Toverifythedesignalgorithmontheelementlevelseveralexperimentalexamplesaredesigned.NonlinearinelasticanalysesareperformedwiththedesignedexamplesusingtheMahmoud-Gupta’scomputerprogramtoshowtheadequacyofthedesignequations.Thecalculatedultimatestrengthsarefrom3to18%higherthantheultimatestrengthobtainedfromthetestresults,exceptinoneexample.Ontheglobalstructurallevel,adesignisperformedforahyperboliccoolingtowertocheckthedesignstrengthtoverifytheadequacyofthedesignalgorithm.Basedontheultimatenonlinearanalysisperformedwiththedesignedreinforcement,theanalyticallycalculatedultimateloadsexceedthedesignultimateloadfrom26to63%foranalyseswithvariousamountsoftensionstiffeningeffect.
Eventhoughtheultimateloadsaredependentonthetensilepropertiesofconcrete,thecalculatedultimateloadsarehigherthanthedesignultimateloadsforthecasesconsidered.Thisshowstheadequacyofthedesignalgorithmdeveloped,atleastforthestructuresstudied.Thepresenteddesignalgorithmforcombinedmembraneandflexuralforcescanbeevolvedasageneraldesignequationforreinforcedconcreteplatesandshellsthroughfurtherstudiesinvolvingtheperformanceofmanymoredesignsandanalysesofdifferentplateorshellconfigurations
