Numerical study on thermal buckling of empty thin-walled steel tanks under multiple pool-fire scenarios

Fire incidents at fuel storage tank farms are high risk incidents due to the fact that can result in severe socio-economic losses, injuries, deaths and have a serious environmental impact. In the case of a tank fire, there is a serious possibility that the fire will spread to adjacent tanks. The research activity in this area is mainly focused on the prediction of the heat transfer characteristics of pool fires, the thermal response of neighbouring tanks (or target tanks) and the potential of fire spreading. On the contrary, the research for the structural integrity of tanks involved in pool fire scenarios is limited. This paper aims to study the thermal buckling behaviour of fixed-roof tanks in the case of pool fire scenarios, considering one or more burning tanks. To this end, different scenarios are examined, aiming to study the key factors (the burning fuel, the wind, the separation distance between tanks and the size of the burning tanks) that may affect the thermal buckling response of the target tanks. Semi-empirical models, available in the literature, are used for the calculation of the characteristics of flames that arise from burning tanks. Then, the problem is solved numerically, through the Finite Element Method. The heat transfer from the burning tanks to the target tank is treated through the open cavity option, and the response of the target tank is predicted in the same thermo-mechanical analysis. The basic objective is the investigation of the inherent fire resistance of thin-walled tanks and to predict their failure.