Study On Anti-blast Performance Of A New Bulkhead Structure

Warship Survivability is a key performance indicator. As for modern military, there is a great demand for study on the destructive power of anti-ship weapons capabilities and anti-blast and anti-blast performance of warships. The research of the development in the new pattern ship protective structures has some important military significance in order to improve the vitality and combat ability. Currently, experiment and finite element simulation and their combination are usually adopted to investigate such problems.Metallic thin-walled tube is a sort of effective energy absorbed structure and is widely applied in energy absorbed systems. The energy absorbed characteristic of the simple square straight and tapered tubes subjected to axial impact were studied firstly in this thesis. The effect of contacting friction factors on the simulation results was then analyzed. Then several tapered built-up structures and straight built-up structures with triggering were introduced from the view of energy absorption capability. Finally, a comprehensive comparative analysis of all the structures was carried out from initial peak load, mean crush load, specific energy absorption. The numerical results have indicated that the absorption capability of built-up thin-walled structures is significantly improved compared with that of the original structures.In the thesis, the numerical simulation on the response of plate bulkhead subject to explosive load was studied by using finite element software ANSYS/LS-DYNA. The simulation results fit very well with the theory formulas. Then a new pattern of built-up bulkhead structure, which is composed of two cross-arranged barriers laid at certain distance after the plate bulkhead and the common plate bulkhead is developed. The anti-blast performance of such new pattern bulkhead structure is further studied from permanent deformation, energy absorption and ultimate bearing capacity. In the analysis, the effects of impact factors and form of barrier structures on anti-blast performance of the structures are analyzed. A comprehensive comparative analysis of the plate bulkhead and built-up bulkhead was carried out from the anti-blast performance. Numerical results show that the anti-blast performance of this new pattern of built-up bulkhead has been greatly improved compared with that of the traditional plate bulkhead structure.