Dynamic analysis of liquid storage tank under blast using coupled Euler-Lagrange formulation

摘要

A growing number of terror attacks all over the world have become a threat to the human civilization. In the last two decades, bomb blasts in crowded business areas, underground railway stations and busy roads have taken numerous lives and destroyed properties in different parts of the world. However, blast response of many important civil infrastructures has still not been well understood due to the complexities in their material behavior, loading and higher nonlinearities. One such example of important civil infrastructure is liquid storage tanks which are undividable parts of any society for storage of water, milk, liquid petroleum, chemicals in industries etc. Blast loading on liquid storage structures may lead to disaster due to water and milk crisis, health hazard owing to the spread of chemicals and fire hazard due to the spread of liquid fuel. Hence, understanding the dynamic behavior of liquid storage structures under blast loading through numerical simulations is of utmost importance. In the present study, three dimensional (3D) finite element (FE) simulations of a steel water storage tank for different tank aspect ratios, percentages of water stored in the tank, tank wall thicknesses, boundary conditions at the bottom of the tank and magnitudes of blast loading have been performed using the FE software Abaqus. The coupled Euler-Lagrange (CEL) formulation in Abaqus has been adopted herein which has the advantage of considering the coupling of structural mechanics and fluid mechanics fundamental equations. The maximum hoop stress and shear stress in the tank wall, the water sloshing heights in tanks and the energy response of the tanks have been studied. It is observed that stresses and liquid sloshing heights in the tank increase with decreasing scaled distance of the explosive material and increasing aspect ratio, i.e. height to radius ratio.