Analysis of the shock effects on a typical foundation structure: experimental and numerical investigation

For naval ships, shock phenomena caused by underwater explosions are demanding limit states not only for machinery and equipment, but also for their foundation structures. Being a crucial part of the system integration, their shock resistance is normally verified by means of dedicated calculations as it is in general not possible the testing of the equipment including relevant structural foundations. Rules allow structural analysis of foundations by finite element method (FEM) dynamic models. However, no detailed modelling strategies, procedures and inputs are provided. The aim of this paper is to study the shock effects on a typical equipment foundation structure, comparing the results obtained by numerical simulation with the data obtained by a series of dedicated shock tests carried out according to the MIL S 901 D medium weight shock standard. Eventually, it is shown that experimental, theoretical and numerical analyses performed in parallel may support each other to provide better understanding of complex phenomena.