Analysis Of The Seismic Behavior Of Bird-beak SHS T-joint

Recent year,steel tube structure has been widely used in various buildings due to its beautiful appearance,light weight,easy fabrication and favorable structure property and other advantage.Joint is one of the crucial memebers of steel tube structure,most of the collapse and destruction of steel tube structure is due to the insufficient strength of its joint.The intersecting joint is one of the common joint form in steel tube structure,and a new type joint which called bird-beak joint is achieved by rotating the chord and brace of a traditional square hollow joint through 45°about their longitudinal axes,but there is a lack of research on the seismic performance of bird-beak joint at present,and it is not clear about its mechanical property under seismic loading.Based on above discussion,this paper made a comprehensive analysis of the seismic performance of the bird-beak joint and ring-stiffened bird-beak joints with finite element software.Bird-beak square hollow T-joint and ring-stiffened bird-beak square hollow T-joints were investigated in this thesis,and the finite elemnt model of the joint were established with ABAQUS,to analyzes the seismic performance of the joint under cyclic axial loading,includig its ultimate bearing capability,hysteretic behavior,deformation performance and failure modes,some inclusions could provide reference for engineering design.The main research contents as follows:(1)Analysed the affect of the parameters of stiffenering ring to ultimate load capacity and stiffness of reninforced bird-beak square hollow joints,and proposed the formula of ultimate load capacity reinforcing multiples of ring-stiffened bird-beak T-joints by the regressing techniques.(2)The mechanical properties of the reinforced joint and the normal joint with same parameters are analysed under the static loading,including the stress distribution,deformation,destruction mode and the different stress paths of the joint.(3)The influence of the parameters of joint to seismic performance was analysed,which contains the hysteresis performance,ductility and energy consumption of the joint.