Objectives   Aiming at the urgent demand for lightweight hangar doors for warships, structural optimization design is carried out in the context of resisting the load of a nuclear explosion shockwave. At the same time, an equivalent test of the principle prototype is carried out to verify its resistance to a nuclear explosion shockwave.

  Methods  Based on the stress characteristics of the door body under a nuclear explosion shockwave, and taking advantage of the light weight and high strength of fiber-reinforced composites, a grid sandwich composite is used as the main lightweight bearing structure, and a fiber pile and dovetail groove are used as the steel-concrete connection structure, thus completing the scheme of the long-span composite door body. On this basis, the shockwave load is equivalent to the static load. According to the principle prototype of large-scale composite materials with a span of 6 meters, the experimental scheme and experimental tooling are designed, and the equivalent full load bearing experiment is completed.

  Results  The results show that the composite lightweight scheme can reduce the weight by more than 30% compared with the steel structure scheme. At the same time, the simulation analysis and equivalent experimental results show that the long-span composite door body has the ability to resist the impact load of a nuclear explosion while meeting the requirements of the corresponding standards.

  Conclusions  The long-span composite door body proposed herein has the characteristics of an obvious weight reduction effect and strong bearing capacity, making it a feasible lightweight scheme for hangar doors (for warships). The equivalent bearing experimental method and experimental results of the principle prototype long-span composite door body have certain reference value for the subsequent application of large-scale composite materials on ships.