Seismic Behavior And Failure Mode Of Semi-Rigid CFST Frames

In this paper, seismic behavior and failure mechanism is investigated throughexperimental study and theoretical analysis of semi-rigid CFST frames structure. Themain research contents include:(1) Through experiments of two semi-rigid CFST Frames under the low level ofreciprocating loads，seismic behavior and failure mechanism of this new type ofcomposite structure was investigated. In these frames, steel beams and CFST wereconnected by end-plates and blind bolts. Vertical axis forces were applied on the top ofpillars and horizontal forces were applied at the end of pillars.(2) Using ABAQUS established FEM of semi-rigid CFST frames. Horizontal load (P)-horizontal displacement (Δ) curves can be got from this model. And comparing withexperimental datas, the accuracy of this model can be evaluated. At the same time,nonlinear full-range analysis was carried out on the specimens, so its failure mechanismand stress distribution law of the key parts can be seen.(3) Establishing FEM of semi-rigid CFST frames under static load, effects ofmechanics parameters on structure and mechanical properties are analyzed. So the maininfluencing factors of the structure properties and law can be got.(4) On the basis of the static performance parameters analysis, choose the factors thathave great effects on elastic stiffness, the yield limit, bearing capacity. Then establishFEM of semi-rigid CFST frames. The influence of different parameters on structuralmechanics performance were analyzed under cycle loads.(5) In this paper, a simplified calculated method of P-Δ curve of semi-rigidCFST frames was established.