Material properties of structural aluminium alloys after exposure to fire

Abstract

Fire safety is one of the major concerns for the design of aluminium alloy structures. In the case of a fire, the temperature of aluminium alloy structural components can rise rapidly, leading to a considerable reduction in their load-carrying capacities. Since fires typically occur in specific areas of a building and may be extinguished before spreading, it is important that the extent of damage and residual material properties of exposed structural aluminium alloys can be quantified. To this end, the residual material properties of structural aluminium alloys after exposure to fire were investigated through an experimental investigation in this paper. A testing programme, including heating tests and 24 post-fire material tests, was performed. Upon completion of the testing programme, the experimentally obtained key post-fire material properties, including the material elasticity, strengths and strains, were analysed through a series of quantitative and qualitative comparisons with their room-temperature counterparts. The analyses and comparisons generally indicate that elevated temperatures have different effects on the key post-fire material properties of structural aluminium alloys. Then, a series of retention factor predictive models were proposed based on the test data, which were shown to provide accurate predictions of the post-fire material properties of structural aluminium alloys.