Post-fire behaviour of 6082-T6 aluminium lap joints

Structural aluminium alloys are subjected to various heat treatments to increase their strength and make them suitable for load bearing applications. During a fire, the beneficial effects of heat treatment can be diminished or completely eliminated, thus necessitating the assessment of the post-fire response of structural aluminium components, since a component may not fail during a fire, but be inade-quate to resist the design loads in the remaining design life of the structure. This paper reports 12 experi-mental tests on 6082-T6 aluminium lap joints subjected to different elevated temperatures before testing. Three distinct configurations employing different bolt spacing were considered resulting in different failure modes (net section fracture, end bearing, a mixture of both). For each configuration, three of the specimens were subjected to elevated temperatures of 200°C, 300°C and 400°C, and then allowed to cool down before testing, whilst a fourth one served as benchmark and was not subjected to elevated temperatures. Additionally, a series of material dogbone coupon tests were conducted to determine the stress-strain beha-viour of 6082-T6 after exposure to elevated temperatures. The obtained load-displacement response, failure load, failure mode and ductility are reported and discussed. The experimental findings are further used to evaluate the accuracy of current design standards used in conjunction with post-fire material properties.