Distribution of temperature in steel and composite beams and joints under natural fire

Parametric numerical analyses have been performed with SAFIR for the temperature distribution in steel and composite beams and joints subjected to natural fires. A simple model has been derived to calculate the temperature development in the upper flange of the steel section supporting a concrete slab. This model takes into account, not only the heat transfer with the surounding hot gases, but also the heat transfer 1) by conduction with the lower part of the section through the web and 2) with the supported concrete slab.