Study of the effects of underwater explosions on the bases of on-board equipment in naval units: Experimental validation of numerical models

Underwater explosions can cause severe damage not only to on-board equipment, but also to their foundations, whose structural properties are critical to ensure the efficiency of the entire foundation-equipment system. Generally, it is not always possible to ensure compliance with shock requirements through experimental tests, therefore, national regulations also allow verification through calculation. In particular, a dynamic analysis using finite element software is accepted. However, the regulations do not specify in detail the modeling strategies and procedures for the calculation inputs. This paper outlines some useful guidelines in the design phase for shock verification. The validation of the proposed modeling methodology is obtained by comparing the results of numerical simulations with experimental tests data, specifically designed and realized using the medium-weight impact machine (MIL S 901 D). Once again, the parallel use of numerical and experimental analyses is essential to better understand such complex phenomena.