Seismic Performance Of Energy-based Steel - Concrete Composite Frame Analysis

In recent years, energy-based seismic design is a hot research project, many researchers conseder it is one of the development direction of earthquake engineering. Also, CFS frame ( steel-concrete composite frame structure ) have been widely applied in various types of construction due to their many seismic advantages. Thus it is very meaningful to do further research on this structure based on energy methods. But little job has been done about its seismic resistant performance in china and overseas. Based on the application and research status for CFS frame, main research work are as follows:1) Compared the result of load-displacement test of steel-concrete composite beams and concrete filled steel tubular columns ,the tri-linear restoring force model with consideration of stiffness degradation was established, which was universal that can be easily applied in energy analysis of layer model in CFS frame.2) Learning from theoretical analysis about energy in other structures, theory of energy analysis and method of energy solutions were established which was applied in the SDOF system of CFS frame, MDOF system of CFS frame and CFS frame system. Based the MDOF system of CFS frame, the program of energy calculation for the layer model was compiled, comparing with the example, the energy method testified the feasibility.3) In this paper, author carries on energy calculation by creation of finite element model of the CFS frame based upon the theory of separation modulus. Considering seismic input motion parameters and structural dynamic parameters, the varied laws of the distribution of CFS frame seismic total input energy,hysteretic energy and damping energy is investigated, also the detailed laws of the storey and the component distribution of the energy is found.4) Discussion of differences of seismic performance and energy dissipation between RC frame and CFS frame is performed by comparing energy analysis of the two structures which is similar to stiffness.5) On the basic of the failure criteria of Park & Ang model failure criteria, one appraise method of seismic behavior on energy to CFS frame structures was put forward.