Abstract: In order to improve the protection ability and damage mechanism of aramid fiber sandwich bulkhead under close range explosion and fragment loadings, the deformation and failure tests of aramid fiber sandwich structure are performed, and TNT and prefabricated fragments are used in the test. The load characteristics of fragments are revealed, and the failure mode of each layer in sandwich structure is analyzed. The anti-damage mechanism of sandwich structure is discussed, and the protection ability of aramid fiber sandwich structure is compared with those of the typical sandwich structures in Ref.\[14\]. The results show that the core layer in the sandwich protective structure plays a role in intermediary transformation of damage load. A fragment point load with small impact area, short duration and severe damage is converted into a pressure surface load with large action area and long duration by squeezing the rear plate, which expands the action range of loads. In view of material weight and protective capability, the protective capability of high strength polyethylene sandwich structure is superior to that of aramid fiber sandwich structure.

Key words: ordnance science and technology, experimental design, fragment load characteristics, failure mode, protective capability