Research On Hysteretic Behavior Of Circle Tubular Steel Members In Single-layer Latticed Shell

Circle tubular steel members are widely used in space frames for their reasonableness of material utilization, good performance on the stiffness and torsion strength. With the increasing widely application of latticed shell structures, the dynamic behavior of such structure has attracted attentions of many researchers. And it is necessary to study the hysteretic behavior of circle tubular in single-layer latticed shell. Considering the characteristic of single-layer latticed shells, the circle tubular steel members with big slenderness ratio in it are subjected to bending moment, shear force as well as axial force. During earthquakes, the changes of both axial forces and bending moments in members are significant. Therefore, the hysteretic behavior of the circle tubular steel members in single-layer latticed shell under constant and varying axial force has been researched in this paper.Using ANSYS infinite element analysis software, numerical analysis models of circle tubular steel members are built with element SHELL181. And the validity of the finite element method adopted to analyze its hysteretic behavior is verified.The hysteretic behavior of circle tubular steel members under constant compression and cyclic bending has been analyzed largely. According to hysteretic curves, skeleton curves, ultimate load-carrying capacity, ductility coefficient, energy dissipation coefficient etc. calculated by ANSYS. The influence of some parameters like slenderness ratios, diameter-to-thickness ratios, and axial compression ratios on the hysteretic behavior of members has been investigated. And a few recommended values of these parameters have been discussed.The loading method of varying compression has been preliminary studied in this paper. The hysteretic behavior of circle tubular steel members under varying compression and cyclic bending has been calculated greatly. The loading capacity, distortion capacity, ductility and dissipation of energy of them are obtained. The characteristics of hysteretic behavior of circle tubular steel members under varying axial force and the influence of the axial force amplitude on hysteretic behavior of members has been researched. At last, the differences in loading capacity, ductility and dissipation of energy between members with constant compression and members with varying compression has been discussed.