Air-Backed Steel Plates Subjected to Underwater Explosion with Strain Rate Effect

The response of unstiffened and stiffened plates to underwater explosion is of great importance for marine structure designers. A shock pressure wave is initiated by the explosion which develops in the water and slams on the surface of the structure plates. An explosion experiment is generally very expensive, and the accuracy of the experimental results depends critically on the performance of the instruments used in the water.A finite element modeling of the structure under the shock pressure wave may help to obtain a good prediction of the submerged structure vibration. This work focuses on the transient dynamic analysis of the stiffened and unstiffened steel plates used in the ship structures subjected to an underwater explosion. The mechanical behavior of the plate is taken as an elastoplastic behavior in which the yield strength of the material depends on the strain rate. The dependency of the yield strength is of great importance since impulsive shock loads are to be applied. The numerical results of the finite element analysis are compared with the experimental results presented in the previous works. Finally, the acceleration, velocity and strain histories of the target plates are acceptably predicted which may be used in the design of the relevant ship structures

Keywords:

Nonlinear dynamic analysis , Underwater explosion , Stiffened plates , Strain rate effect