ABSTRACT

Abstract A natural fire test was performed in a classroom of 60 m2 within a two-storey steel building. The internal enclosure of the classroom was built with two plaster board partitions and a vermiculite board partition, incorporating two wooden doors. The steel profiles located inside the classroom were insulated by 25 mm of sprayed fire protection material. The temperature within the classroom reached 1200 °C. The fire lasted about 45 min and remained localised in the classroom. A maximum steel temperature of 350°C was obtained in the edge columns which were not insulated on their external flanges. By using numerical models for a global assessment of the behaviour of buildings in natural fire (fire model, heat transfer model and mechanical model) a good accuracy with experimental results was obtained. Keywords: Fire, steel.