Destroy Research The Defendence Structure Near Shipboard Of Warship Subjected To Underwater Contact Explosion

The dynamic response of the ship shell, which is caused by the impact loads of underwater contact explosion, is one of important parts in the anti-detonation design of ships. It can improve the defensive capability and the survivability of the ships through doing thorough research. At the same time, the numerical simulation technology has also provided the broad prospect for the underwater anti-detonation research with the rapid development of computers.The analysis of damage and the reliability research of defence structure near shipboard of giant surface warship subjected to the underwater contact explosion impact loads were carried out in this article. It was to understand the fail mechanism of defence structure near shipboard further and to improve the defensive capability of ships. In research the theoretical analysis method and the numerical simulation method were adopted together.The defence structure near shipboard of giant surface warship is a complex multilayered plate girder structure. The destruction mechanism of this structure is studied when the underwater contact explosion loads were applied; From the point of view of energy, the defence function of vacant cabin and liquid cabin of each layer was analyzed, and the crevasse radius of every layer of plate girder and the biggest deformation of the inner layer of plate girder were deduced separately.The analysis was done by the finite element software LS-DYNA. The dynamic responses of the defence structure near shipboard of naval ship were simulated when they were suffered attack. One case is that it was attacked by weapons at one time. The other is that it was attacked by weapons successively. The influences with different stiffened types were considered at the same time. Results were obtained, that increasing the size of the vacant cabin of defence structure was better than liquid cabin, and the damage caused by weapons successively was more serious than by weapons together.When calculated the reliability of the defence structure near shipboard of naval ship, Monte Carlo was used for getting the sample data. Simultaneity the influences caused by different factors were considered such as the parameters of explosive and the material of ships and so on. The maximal stress of each layer was gained by resorting to numerical simulation using the intensity criterion. Then the distribution function was got. Finally the destruction probability was worked out.