Analysis of ultimate capacity of sandwich composite material against impulse load: A study case of fluid-structure interaction by FE approach

Composite materials are increasingly used in maritime environments due to their lightweight properties, corrosion resistance, and excellent mechanical strength. However, the main challenge is their ability to withstand extreme marine conditions, such as impact loads from waves striking the structure. This study aims to evaluate the ultimate capacity of sandwich composite materials under impulsive loads to assess their performance and optimal configuration for maritime applications. Numerical simulations were conducted using the Finite Element Method (FEM) based on the validated methodology from a laboratory experiment data. The analysis was per formed using varying parameters such as material type, number of layers (stacking), and core thickness. The structural performance was evaluated by observing the midpoint displacement as the primary indicator of the response to impulsive loading. The results indicate that composites with a metal matrix exhibit the lowest midpoint displacement, reflecting superior structural performance to non-metal matrix composites. Increasing the number of layers significantly enhances structural strength, with the most notable improvement occurring from one to two layers. Additionally, greater core thickness consistently reduces midpoint displacement, improving resistance to impulsive loads. CFRP material with three stacked layers and a core thickness of 28 mm demonstrated performance comparable to AL/Al Foam, making it a viable alternative material for maritime environments. This study provides valuable insights into the optimal configuration of sandwich composite materials for resisting impulsive loads in maritime applications. This research contributes to developing more reliable composite materials for structural applications in the maritime sector by presenting simulation-based analyses validated through experimental data.