Research on overall damage characteristics of a hull girder under explosion bubble collapse

摘要

The deformation mechanism of warships subjected to underwater explosion is very important to the survivability assessment of warships. Therefore, in this study the deformation mechanism of a hull girder similar to a real warship structure subjected to underwater explosion loads has been investigated experimentally and numerically. In addition, the non-spherical effect of underwater explosion bubble is considered. The experiment is conducted in a water pool of underwater explosion, and the numerical calculation is carried out through the Coupled Eulerian-Lagrangian (CEL) algorithm. Then the validation of the method is conducted and numerical results agree well with the experimental results. After that, the detailed discussions on the overall damage characteristics of a hull girder under explosion bubble collapse are implemented. Finally, a series of cases are conducted to investigate the response of the hull girder under different underwater explosion conditions. By analyzing the experimental and numerical results, conclusions can be drawn that with detonation distances decrease, the deformation form of the hull girder converts rigid-body motion to whipping and a plastic hinge generates. When the charge weights are in a certain range, the dynamic responses of the hull girder are similar for different charge weights with same dimensionless distance.