Study on the influence factors of the bearing characteristics of the ship with an integrated glass fiber sandwich composite superstructure.

The research object is a scaled ship model based on the actual size of the naval ship. The ship model's superstructure is made of fiberglass sandwich composite structure and integrated design method. Firstly, based on the theory of composite sandwich panel, the magnitude and distribution of stresses and deformations of the measuring points on the model are analyzed by using the static loading test with four-point bending method under the hogging and sagging cases. The work finds that when the integrated superstructure participates in the total longitudinal bending of ships, its sandwich composite material structure has low stress and coordinated deformation. Therefore, when there are no elastic joints, the superstructure can be constructed into a continuous integrated structural form. After that, the composite stiffness degradation correction model is proposed, the USDFLD subroutine for the failure criterion of the composite shell elements is written, and the damage modes, damage regions and extension paths of the superstructure are obtained by applying different proportions of displacement loads and calculating based on the finite element model of progressive damage. Finally, the work further analyzes the influence of the thickness and orientation of fiber layer in skin, the structural materials of superstructure, the material types and layup thickness of stiffeners in superstructures, and the structural form with or without deck opening and transverse bulkheads on the bearing characteristics and mechanical properties of the integrated superstructure. • Sandwich composites show low stress in ship bending. Non-elastic joints enable continuous structural form. • The study found transmission traits of the composite superstructure vertically and at the hull interface. • The study introduces a composite degradation model, USDFLD subroutine, and analyzes damage in the superstructure. • Showing how factors like skin thickness, layering, material, and structure affect load-bearing. [ABSTRACT FROM AUTHOR]