Objective  In order to improve the anti-shock perfomance of ships subjected to underwater explosion, this paper studies the energy absorption and impact resistance of the new protective structure consisted of carbon fiber reinforced plastic (CFRP)-lattice aluminum sandwich plates.

  Methods  First, finite element software ABAQUS is used to establish the numerical simulation model of CFRP-lattice aluminum sandwich plates under non-explosive and non-contact underwater explosion load, and its reliability is verified. Single variables are then controlled to analyze the influence of the fiber layer thickness of the upper and lower panels and the rod diameter of the sandwich lattice structure on the energy absorption characteristics and structural deflection of the CFRP-lattice aluminum sandwich plates. Finally, based on the above three design parameters, a surrogate optimization model is established using the experimental design method and numerical simulation methodology to optimize the energy absorption of the CFRP-lattice aluminum sandwich plate structure.

  Results  The results show that when the mass of the CFRP-lattice aluminum sandwich plates is constant, the specific absorption of the optimized results can be increased by 284%. In full consideration of the deformation of the lower plates, the specific energy absorption of the optimized results can be increased by 59%.

  Conclusions  This study shows that the proposed optimized structure of CFRP-lattice aluminum sandwich plates can effectively improve their energy absorption capacity, and the response surface method is an optimization method that can effectively improve the energy absorption characteristics of the structure.