Study On The Mechanical Properties Of Conical Double Skin Steel Tube Confined Concrete Stub Columns Subjected To Axial Local Compression

How to reasonably design conical double skin steel tubes confined concrete stub columns isone of the hot topics in the relevant engineering field now.It was not solved in the past designcode yet.The related research needs to do further, especially theory research.The research onconical double skin steel tubes confined concrete stub columns under axial local compression isnot reported to date.Behaviours and mechanism of conical double skin steel tubes confined concrete stub columnsunder axial local compression were investigated in this paper, including theoretical andexperimental studies. Based on the systemic analysis of parameters, practical computationalmethods for axial local compression bearing capacity of conical double skin steel tubes confinedconcrete stub columns were given.In this paper, the main achievements were summarized in detail as follows:Cone angle and the local compression area ratio were chosen the main parameters.Experimental studies on the behaviours of conical double skin steel tubes confined concrete stubcolumns under axial local compression were carried out, including10specimens.The differencesbetween cone angle and local compression area were compared.Based on a large amount of computational examples, load-deformation curve of CFST underlocal compression was obtained by ABAQUS, which is a common analysis software by finiteelement method (FEM). Since verified lots of tested results, it demonstrated that the numericalmethod is reliable in predicting the load versus deformation relationships.Load-deformation curves of conical double skin steel tubes confined concrete stub columnsunder local compression were analysized through the computational method given by this paper.The influence of cone angle, local compression area ratio, concrete strength, steel tube strengthand thickness was investigated. It is the original work that the axial local compressionmechanism of conical double skin steel tubes confined concrete stub columns was discovereddeeply.On this basis, the method to calculate the axial local compression bearing capacity wassuggested.The results indicate that the method has clear mechanics concept, and easy using,which can supply practical engineering and specifications with reliable references.