RESEARCH ON RESTORING FORCE MODEL OF CONCRETE FILLED STEEL STUB STRUCTURE

摘要

Concrete filled steel tube (CFST) structure is a new type of structure. According to unified theory, hysteretic model of steel beam and CFST column have been chosen respectively, then nonlinear structural analysis program called ID ARC is employed to determine restoring force model of the CFST structure. Results obtained from the program are consistent well with those obtained from experiments. Furthermore, some parameters that affect the restoring force model of CFST structure have been studied, including axial compression ratio, steel ratio, material strength and so on. The results not only provide necessary theory basis for popularizing the CFST structure but play a valuable role to seismic design of CFST structure. The contribution described herein outlines a possibility for simulating the behavior of CFST using the nonlinear program called IDARC. The present work offers a simplified approach for establishing the skeleton curves of CFST frames.