Dynamic response of warship structure under air non-contact explosion

The ship hull is simplified as a free beam with varying sections. Based on hydroelasticity and explosion mechanics theory, mechanical model and kinetic equation for hull girder vibration under non-contact explosion are established. The equation is solved by Wilson-θ algorithm. On the basis of the above principles, a structure kinetics analysis program is compiled. The dynamic response of supposed warship under air explosion is calculated conveniently and quickly. Under the explosion condition designed in the paper, the positive pressure period of non-contact explosion wave is much less than the natural periods of the first four modes of hull girder and the resonance of ship girder overall vibration can be avoided. The ratio of midship maximum moment to ultimate bearing strength under non-contact explosion accelerates with the increment of impact factor.