Entire loading procedure analysis of concrete-filled steel tube column to steel beam joints under fire

This paper presents a finite element analysis (FEA) model to study the mechanical performance of circular concrete-filled steel tube (CFST) column-steel beam joints with reinforced concrete (RC) slab under combined temperature and load. Tests on this kind of joint exposed to ISO-834 standard fire are carried out to verify the FEA model. The accuracy of the predicted result is generally acceptable. Based on the FEA model, the moment versus relative rotation between column and beam curve in the full range including ambient, heating, cooling and post-fire phases is calculated, and the stress distributions of core concrete and steel beam in joint zone at different feature time points during the above four phases are analyzed