Mechanical behaviour of full unit masonry panels under fire action

An analytical model is presented to predict the mechanical resistance of full unit masonry panels under combined compressive and bending stress, in the presence of a nominal fire acting on one side. Transitory thermal analysis of the panels is conducted, while accounting for the convection and radiation effects produced by the fire, to determine the collapse conditions for combined compression and bending; five strain field collapse configurations are considered. The numerical analyses, based on data drawn from European regulations EN 1996-1-2, permit the determination of the M–N crushing domains for brick and lightweight aggregate concrete masonry walls, with various thicknesses and exposure times to nominal fire. A numerical example demonstrates the applicability of the model, and a comparison with a set of experimental data on masonry panels demonstrates the efficiency of the model.

► Transitory thermal analysis of the masonry panels is conducted.
► Five strain field collapse configurations are ideated.
► The axial force–bending moment crushing domains in function of the time of exposure are determined.