ABSTRACT

This paper presents a numerical investigation of Carbon Fiber Reinforced Polymer (CFRP) strengthened and unstrengthened cold-formed steel tubular columns to determine the maximum temperature that a column can sustain for a given service load factor. Finite Element (FE) models were developed and validated by comparing axial compression test results from an ongoing exeperimental study. Validated models were used to determine the failure loads of CFRP strengthened and unstrengthened columns at elevated temperatures by incorporating the elevated temperature mechanical properties of CFRP and cold-formed steel tubular sections. Results showed that CFRP strengthened tubular columns displayed a significant capacity reduction with temperature than unstrengthened tubular columns. Therefore, this paper shows that the fire performance of CFRP strengthened steel tubular columns is worse than that of unstrengthened columns for a given service load roatio and thus emphasizes the importance of an insulation system to protect the CFRP strengthened steel columns in fire events.