ABSTRACT
This paper presents an experimental investigation undertaken to measure the elevated temperature mechanical properties of cold-formed steel tubular sections. Tensile coupon tests at temperatures ranging from 20ºC to 800ºC were conducted to determine the reduced values of elastic modulus, yield strength and ultimate strengths with increasing temperatures. Based on the test results, suitable equations were proposed to determine the mechanical property reduction factors at elevated temperatures. These reduction factors along with the factors given in the current design codes were then used in the numerical modelling of stub columns to determine their failure loads at various elevated temperatures. The failure loads predicted using the reduction factors in the current design codes resulted in unacceptable differences compared to the proposed, more accurate reduction factors. This shows the importance of using the measured mechanical property reduction factors in the fire design of cold-formed steel tubular sections.
