Response of shielding structures to explosive loading

This paper presents the results of a numerical and experimental study of the behaviour of a brass hopper held in a supporting structure subjected to internal explosive loading. The structure is typical of those employed during the manufacture of explosive accessories. In such processes the hopper acts as a feed for the explosive while the encasing structure both supports the hopper and provides protection to the surroundings in the event of accidental initiation. The finite element model includes representations of the explosive, the brass hopper and the steel supporting structure. The boundaries between the components are treated as sliding and separable interfaces. Analysis is performed using the Oasys DYNA3D (version 5.1) finite element program. The numerical predictions for the deformations are compared with test results. The DYNA3D finite element code is shown to be an effective tool for the appriasal of this type of protective structure under explosive loading. Both the numerical and experimental studies point the way to improvements in the current design.