Study on the Influence of Structural Dimensions on Plate Deflection Under Confined Blast

The damage assessment of structures subjected to confined internal blast remains a focal point in the field of explosion. However, current research results are mostly limited to the situation where the cabin structure dimensions remain constant, and the influence of cabin structure dimensions on damage effect under internal blast has not been systematically considered. In order to study the influence of structural dimensions on deformation and deflection of plate under confined blast loadings, LS-DYNA R11.1 finite element simulation software was used, based on a fluid–structure interaction (FSI) algorithm, to carry out simulation research on blast under different cabin structure parameters. The propagation law of blast shock waves under different cabin structure parameters was analyzed, and the deformation and deflection of the plate at the end of the cabin under different explosion equivalent and explosion point positions were studied. The results indicate that when the mass of the explosive remains constant, the location of the explosion point and the structural parameters of the cabin are the main factors affecting the deformation and deflection of the plate. When the distance between the explosion point and the proximal plate is the same and the aspect ratio is 2, the deflection of the proximal plate is smaller than that of the distal plate. When the aspect ratio is 3, as the distance between the explosion point and the proximal plate increases, the deflection of the proximal plate gradually increases, while the deflection of the distal plate first decreases and then increases. When the aspect ratio is 4, 5, and 6, as the distance between the explosion point and the proximal plate increases, the deflection of the proximal plate first increases and then decreases, and the deflection of the distal target plate first decreases and then increases. The research results can provide some reference for the damage assessment of internal blast in structures and the design of structural protection.