Computational Study of Steel‐Timber Composite Beam Under Fire Condition

Abstract The combination of steel and timber in composite systems enhances material performance and provides greater flexibility for structural design. While steel beams offer high strength, they are particularly susceptible to lateral‐torsional buckling and the adverse effects of elevated temperatures during fire exposure. Timber elements, on the other hand, can serve as passive fire protection and offer lateral restraint to steel members. In this context, the present study investigates the fire resistance of steel‐timber composite (STC) beams through a computational approach. The research employs the SAFIR ® software to perform both thermal and thermomechanical analyses, focusing on two STC beam configurations and a reference steel‐only beam. The numerical models simulate the behavior of these beams under standard fire conditions (ISO 834‐1), with the results validated against experimental data available in the literature. The analyses assess temperature distributions, displacement responses, and critical failure times. The findings demonstrate that the presence of timber as thermal protection significantly improves the fire resistance of the composite beams. Moreover, the numerical methodology developed offers a reliable tool for studying the structural performance of STC systems.