Research On Torsion Of Cfst-CSW Members And Spacial Behavior Of CFST-CSW ARCH

Concrete filled steel tubular structure with corrugated steel web (CFST-CSW) is a typeof newly proposed composite structure, in which the CFST members carry the main actionsand CSWs are utilized as connection components. It has the advantages of the highcompression strength of CFST and shear resistance of CSW simultaneously. However, theprevious research only focused on ultimate load-carrying capacity of in-plane bending ofCFST-CSW girders, axial and eccentric compressive columns, and in-plane loading ofCFST-CSW model arch. Therefore, in order to improve the basic mechanical behavior of thisstructure, a systemic research with an emphasis on torsion of CFST-CSW members andspacial load of CFST-CSW arch is carried out in this thesis, focusing on experimentalinvestigation, finite element analysis. The main tasks in this thesis include the following:Experimental investigation on CFST-CSW members subjected to torsion is carried out.The test results have been analyzed to understand the behavior of CFST-CSW members undertorsion. Furthermore, the behavior of CFST truss member and PC composite box memberwith CSW under pure torsion were compared with the CFST-CSW member. Utilizing thegeneral purpose program ANSYS, the finite element method for analyzing CFST-CSWmembers is proposed. And then, the effect of different parameters on torsional capacity isinvestigated, including web thickness, tubular thickness of chord, grade of in-filled concrete.The result shows that the torsion is mainly carried by CSW for CFST-CSW(B) memberswhich have a strong torsional bearing capacity, anti-deformation ability and ductility.Moreover, increasing the web thickness and the tubular thickness of chord will improve thetorsional bearing capacity for CFST-CSW(B) members significantly. Based on theexperiment, finite element analysis, the simplied calculation method regarding the torsionalbearing capacity of CFST-CSW members is proposed which can make a reference fortheoretical research and engineering design.Experimental investigation on CFST-CSW model arch subjected to spatial loading wascarried out. Utilizing the general purpose program ANSYS, the finite element model foranalyzing CFST-CSW arch is established. The result shows that failure modes of model archis mainly controlled by out-plane deformation. The dual none-linearity should be took into accont to analyze the mechanical behavior of whole process of CFST-CSW model arch. Inaddition, the torque is so much less than the out-plane bearing moment when the model archsubjected to spatial loads. Therefore, the effect of torsion to the overall carrying capacity canbe reasonaby neglected.