Calculation of the fire resistance of composite concrete floor and roof slabs

A calculation method is described for the determination of the fire resistance of composite floor and roof slabs. Using this method, simple approximate formulas are derived for the calculation of the thermal fire resistance and minimum cover thickness to the steel of reinforced and prestressed concrete slabs, consisting of two layers of concrete, one lightweight and one normal weight. Comparison with test results shows good agreement between calculated and experimental fire resistances.La publication pr\ue9sente une m\ue9thode de calcul de la r\ue9sistance au feu des planchers et des dalles de toits composites. A partir de cette m\ue9thode, on a \ue9tabli des formules simples pour le calcul de la r\ue9sistance au feu et de l'\ue9paisseur minimale du b\ue9ton recouvrant l'armature dans les dalles de b\ue9ton arm\ue9 et pr\ue9contraint compos\ue9es d'une couche de b\ue9ton l\ue9ger et d'une couche de b\ue9ton ordinaire. La comparaison avec les r\ue9sultats d'essais d\ue9montre la similarit\ue9 entre le r\ue9sistance au feu calcul\ue9e et celle obtenue \ue0 partir d'essais.Peer reviewed: YesNRC publication: Ye