Dynamic Response of Stiffened Plates Subjected to Underwater Shock Loading

Abstract

The dynamic response of a floating structure subjected to underwater explosion is greatly complicated by the explosion of a high explosive, propagation of shock wave, complex fluid–structure interaction phenomena, and the dynamic behavior of the floating structures. A numerical investigation has been carried out to examine the behavior of stiffened steel plates subjected to shock loads resulting from an Underwater Explosion (UNDEX). The aim of this study is to enhance the dynamic response of stiffened plates to resist underwater shock loading. A non-linear dynamic numerical analysis of the underwater explosion phenomena associated with different geometrical stiffened steel plates is performed using theABAQUS/Explicit finite element program which provides an important analysis tool that can help engineers and designers to design and construct better structures to resist shock loads. Special emphasis is focused on the evolution of mid-point displacements and the maximum displacements. Further investigations have been performed to study the effects of including material damping and the rate-dependent material properties. The results obtained show that the inclusion of a damping material can absorb energy under blast load. It helps to reduce the force transmitted to the main structure. The inclusion of damping material helps to reduce the displacement of the plates. The results indicate that stiffener configurations affect greatly the overall performance of tested steel plates. The displacement–time histories are presentedwhich will be used in designing stiffened panels so as to enhance resistance to under water shock damage. The obtained numerical results can help in proposing design guidelines for floating structures in order to enhance the resistance to underwater shock damage, since explosive tests are considered costly and dangerous.