Class 4 stainless steel I beams subjected to fire

•Sensitivity analysis of the influence of geometrical imperfections and residual stresses on the numerically determined ultimate load bearing capacity of stainless steel Class 4 beams.•Numerical parametric study on beams with lateral-torsional buckling and local buckling.•Evaluation of different design equations proposals for stainless steel Class 4 beams in case of fire.

Structural elements composed of Class 4 sections are common in stainless steel buildings structures. These thin walled profiles are more susceptible to the occurrence of local buckling. Additionally, in beams the lateral-torsional buckling is also a common failure mode. These instability phenomena are intensified at high temperatures. This work has the main objective of presenting a numerical study on the fire behavior of beams with Class 4 stainless steel sections when subjected to pure bending and high temperatures. The influence of several parameters, as geometrical imperfections and residual stresses, on the ultimate load will be evaluated and comparisons between the numerical results and the Eurocode 3 rules will also be made.