Investigating the behavior of above-ground concrete tanks under the blast load regarding the fluid-structure interaction

The possibility of damage caused by explosive loading in above-ground tanks due to not being covered is much higher compared to buried and semi-buried concrete and steel tanks. In order to evaluate the real behavior of above-ground tanks, it is necessary to pay attention to fluid and structure interaction. Therefore, investigating the behavior of above-ground tanks under the blast load, taking into account the effects of fluid-structure interaction is the main goal of the study. For this purpose, the main variables are the amount of fluid in the tank (empty, half full, and full) and the distribution of fluid pressure on the tank (uniform and nonuniform pressure). Also, the investigated responses include maximum von Mises stress, maximum displacement created in the tank, kinetic energy, and failure index. The results show that considering the tank as empty of fluid, increased the responses of maximum stress, maximum displacement, kinetic energy, and failure index by 18.1, 31.2, 4.1, and 17%, respectively. Also, filling the tank with fluid has caused a decrease of 41, 90, 8.9, and 15.4% in the responses of maximum distributed stress, maximum displacement, kinetic energy, and failure index of the tank, respectively. Other results show that the nonuniform distribution of fluid pressure in the tank increases the maximum responses of stress and failure index in the tank by 35.6 and 2.5%, respectively. In this condition, the maximum responses of displacement and kinetic energy decrease by 84.3 and 4.3%, respectively.