Component-based approaches to steel and composite joints in fire

Abstract

When subject to fire steel loses both strength and stiffness. It also expands when heated and contracts on cooling. Thus the effect of restraint to thermal movement of a steel member can introduce high strains in both the member and the joints at its ends. Fire tests on steel structures have shown that the temperatures within joints are lower during heating than those of the connected steel members. This is due to the additional material around a joint (the column, end-plate, concrete slab etc.) which significantly reduces the temperatures within the joint compared to those at the mid-span of the supported beam. [Excerpt from Introduction}