The Seismic Response Analysis Of Multilayer Steel-concrete Composite Structure Basing On3D Finite Element Models

A great deal of experimental study and theoretical research of the static behavior of the steel-concrete composite structure has been done domestic and overseas, but the seismic behavior of the steel-concrete composite structures under seismic wave is mainly studied by experiments, with theoretical analysis as supplement. In this paper the finite element(FE) method is used to analyse the seismic and static behavior of the steel-concrete composite structures. The research contents are mainly as follows:(1)A plastic concrete damage constitutive model and a steel mixed hardening model which are suitable for ABAQUS were chosen. By presenting nonlinear FE analysis of steel-concrete composite beam, steel beam of CFST connection, steel beam of CFST column frames using ABAQUS,3D finite element models were built, and the calculated results were compared with test results. It can be verified that the constitutive model chosen is suitable for the analysis of the seismic behavior of steel-concrete composite structures.(2)Models of the two-layer single-span single-bay concrete slab I steel beam-CFST column frame were established, based on which3D finite element models under various peak accelerations of the seismic wave were built, and the calculated results were compared with test results. Through typical examples, the time history analysis under seismic wave and the influence of the number of shear connector component of the steel-concrete composite beam-CFST column frame was analyzed.(3)3D finite element models of the concrete-filled dumbbell-shaped steel tubular middle long columns under axial load were built, and the influence of the slenderness ratio, steel ratio, concrete strength and yield of steel strength of the stability of the concrete-filled dumbbell-shaped steel tubular middle long columns under axial load was mainly analyzed. A practical calculating formulation of stability capacity suitable for concrete-filled dumbbell-shaped steel tubular middle-long columns under axial load was suggested.