[en] One of the most important advantages of using the slim or integrated floor beams (SFB and IFB supporting full concrete slab, precast units or steel deck composite slab) is a significant fire resistance. However, despite of its common use in construction, no specific simplified calculation methods for the fire resistance of IFB and SFB exist in the Eurocode.
This study, based on existing calculation rules of Eurocode 4, a parametrical study using soft-ware SAFIR and fire tests results, define a set of formulas to determine the thermal field and to deduce the mechanical resistance from classical plastic design.