FINITE ELEMENT ANALYSIS ON FIRE EXPOSED CONCRETE-ENCASED CFST COLUMN SUBJECTED TO CYCLIC LOADING

A finite element analysis (PEA) model for fire exposed concrete-encased concrete-filled steel tubular (concrete-encased CFST) columns under cyclic loading is established in this paper. During the full-range loading process, the column resists constant axial load under ambient temperature, and then the heating and cooling stages are applied while the axial loading is kept constant. The thermal expansion, transient thermal strain and thermal creep of materials are also considered in the numerical model. The proposed FEA model is validated using previous test results. The temperature field is analyzed for the column exposed to fire. Meanwhile, the comparison is also made on the seismic behavior of concrete-encased CFST column before and after lire exposure.