Non-Rigid Behavior Of Circular Tubular Joint

Steel tubes have widely used in public halls with large span and medium-to-high rise building. Connections between hollow section steel tubes are usually configured by welding one member directly to the surface of the other. However, the loaded braces always cause local distortion of the chord cross-section and hence displacement and rotations of the ends of the braces relative to the chord axes. Non-rigid behavior of this kind of joints will redistribute the nominal stresses, increase the deflections, and influence the buckling loads of steel tubular structure.At present, analysis of tubular joints is based on some theoretical analyses and experiments. In this thesis, the large-scale general finite element analysis software ANSYS is applied in rigidity analyses of the new gymnasium of Shanghai Jiaotong University.Firstly, systematical researches are performed on identification and determination of parameters influencing non-rigid behavior of tubular joints. Rigidity of tubular joints is defined according to their deformation mechanism. Then finite element analyses are conducted on many tubular joints. Results indicate that the parameters which most affect joint rigidity are brace-to-chord diameter ratio, brace-to-chord thickness ratio and the angle between brace and chord.Then, finite element analyses are conducted on joint specimens based on...