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

Objectives To solve the problem of applying thick carbon fiber laminates in naval architecture and marine Engineering, a thick plate structure with reinforcing ribs and core material in the middle composed of thin carbon fiber laminates is proposed.

Methods Firstly, Based on the theory of continuous damage mechanics, two-dimensional Hashin failure criterion and cohesive element technology, the finite element analysis model of combined thick plate is established. Secondly, compare and analyze the bending performance of combined thick plate in different directions.Then, 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. The influence of adhesive strength on the damage behavior of the combined thick plate is also discussed.

Results The results show that the bending stiffness of 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 the panel is the first to suffer damage, rapidly expanding 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 weak, the adhesive layer breaks first; When the adhesive strength is strong, the laminates breaks first. The adhesive layer mainly bears shear action under type II and III tearing modes, and the shear stress in the direction of reinforcing rib is the main reason for the initial damage of the adhesive layer.

Conclusions Research on the damage behavior of a new type of combined thick plate during bending perpendicular to the stiffener direction, providing technical reference for the promotion and application of thick composite plates with reinforcing ribs and core material in the middle in major load-bearing structures in naval architecture and marine Engineering.