Large-scale fire test of unprotected cellular beam acting in membrane action

This paper describes a full scale fire test performed recently on a composite floor for analysing the possibility of tensile membrane action to develop when the unprotected steel beams in the central part of the floor are made of cellular beams. The natural fire was created by a wood crib fire load of 700 MJ/m² and the 9 x 15 m floor survived the fire that peaked at 1000°C and lasted for about 90 minutes. Blind predictions of the air temperature development by the software OZone and of the structural behaviour by the software SAFIR which proved quite satisfactory are also described