Objective The critical compartments of deep-sea large-scale scientific facilities must withstand nuclear explosion impacts. Traditional steel structures struggle to balance lightweight design, low space occupation, and high blast resistance. This paper proposes a novel sandwich bulkhead design incorporating a negative Poisson's ratio corrugated-tube metamaterial that enables quasi-static conversion of impact processes.

Methods The mechanism of a 3D negative Poisson's ratio corrugated-tube metamaterial capable of converting nonlinear impact into quasi-static processes is introduced. Under the constraint of similar weight and space occupation, both a sandwich bulkhead incorporating this metamaterial and a conventional bulkhead are designed for the facility's key protective compartment. LS-DYNA parametric analysis is employed to optimize the unit cell angle and wall thickness. Based on the nuclear blast load specified in GJB1060.1, numerical simulations are conducted to analyze the influence of unit cell angle and wall thickness on impact resistance.

Results The optimal protective performance is achieved with a unit cell wall thickness of 0.6 mm and an angle of 21.250°. Compared with the conventional bulkhead, the maximum impact displacement of the metamaterial sandwich bulkhead is reduced by 58.53% and the maximum reduced by 14.25%, with lower weight and space occupation. The stress remains below the yield strength of H36 steel (370 MPa), satisfying elastic design requirements.

Conclusion The corrugated-tube metamaterial can significantly reduce stress and deformation without increasing weight, achieving elastic design and providing a directly implementable solution for lightweight anti-nuclear blast protection in ship and ocean engineering applications.