ABSTRACT
Design recommendations for Concrete Filled Steel Tubular (CFST) continuous columns in fire are limited, as all experimental testing of CFST members reported in the literature has been on columns where the same temperature is applied to the column over the full column height. The author’s research has focused on columns that are continuous past the heated zones. Experimental test carried out on continuous concrete filled steel tubular columns by the author were used in validating the advanced numerical analysis carried out in this paper. This work has shown that the analysis of a column in a multi-storey building as an isolated member, even taking into account end rotational stiffness in effective length determination, produces a conservative result when compared to a similar column that has been analysed as a continuous column. The research output was used to develop a simple design equation to calculate the axial capacity of CFST columns in fire and this was used to design the CFST column used for the Auckland International Airport Limited (AIAL) Phase 4 Pier B Extension project, for a 60 minutes fire rating.
