The effect of high-temperature creep on buckling behaviour of aluminium grade EN6082AW T6 columns

The paper presents an experimental study that investigates the influence of high-temperature creep on reduction of the buckling load capacity of aluminium grade EN6082AW T6 columns. The study was performed by performing constant-temperature capacity and creep tests on 17 column specimens of approximately 2.6 m length. A total of eight capacity tests and nine creep tests were carried out. Results obtained within the study have revealed a critical temperature interval of 160–260 °C within which high-temperature creep significantly influences the columns' buckling load capacity. The load level at which high-temperature creep influences the reduction of columns' buckling-load capacity, by exhibiting low short-term creep resistance, is above 90% of the column's axial load capacity. The study provides relevant thermo-mechanical criteria for the assessment of creep-induced buckling of the tested aluminium alloy, in the form of the load level intervals at prescribed temperatures, which induce column buckling within the 240 min interval that is generally considered as a relevant fire resistance period for building structures over 18 m in height.