Analysis of damage behavior of new-type marine composite thick plate with reinforcing ribs and core material in middle

ObjectivesTo solve the problem of applying thick carbon fiber laminates in naval architecture and marine engineering, this paper proposes a thick plate structure composed of thin carbon fiber laminates with reinforcing ribs and core material in the middle.MethodsFirst, based on the theory of continuous damage mechanics, two-dimensional Hashin failure criterion and cohesive element technology, a finite element analysis model of a combined thick plate is established. Second, the bending performance of the combined thick plate in different directions is compared and analyzed. Next, the progressive damage process of the adhesive layer and carbon fibre-reinforced polymer (CFRP) is analyzed to investigate the failure behavior and mechanisms of the combined thick plate during the bending process in the direction perpendicular to the stiffeners. Finally, the influence of adhesive strength on the damage behavior of the combined thick plate is discussed. ResultsThe results indicate that the bending stiffness of the combined thick plate is higher in the direction perpendicular to the stiffeners compared to the parallel direction. During the bending process perpendicular to the reinforcing rib direction, the adhesive layer at the interface between the rib plate and panel is the first to suffer damage; it rapidly expands under shear force, ultimately forming a mixed failure mode where interface failure and panel 0° ply fiber tearing promote each other. When the adhesive strength is low, the adhesive layer breaks first; and when the adhesive strength is high, the laminates break first. The adhesive layer mainly bears shear action under Types II and III tearing modes, and the shear stress in the direction of the reinforcing rib is the primary cause of initial damage to the adhesive layer. ConclusionsThis study reveals the damage behavior of a new-type composite thick plates during bending perpendicular to the stiffener direction, thereby providing technical references for the promotion and application of thick composite plates with reinforcing ribs and core material in the middle in major load-bearing structures in the fields of naval architecture and marine engineering.