The fire behaviour of multi-bay, two-way reinforced concrete slabs

This paper describes numerical modelling of the fire behaviour of two-way reinforced concrete slabs in a multi-storey multi-bay building. The building is square, with three bays in each direction. The concrete slab is supported by a perimeter frame, four internal columns and no internal beams. It is assumed that all nine bays of the concrete slab at one level are subjected to fire from below. Two fires were used; the standard ISO834 fire for a four hour duration, and a parametric fire based on the ISO834 fire for one hour with the temperatures decaying to ambient in another two hours. The effects of the fires are described in relation to the redistribution of bending moments and the development of tension field action in the slab.