Fiber-Reinforced Composites and Crack Propagation in Marine Hull Panels

Abstract

The transition from traditional metallic structures to advanced composite materials in marine engineering has introduced unparalleled advantages in terms of strength to weight ratios, corrosion resistance, and hydrodynamic efficiency. However, the application of fiber reinforced composites in marine hull panels presents complex challenges concerning structural integrity, primarily due to their susceptibility to interlaminar and intralaminar crack propagation under severe environmental and dynamic loading conditions. This paper presents a comprehensive experimental analysis aimed at characterizing the fracture behavior and crack propagation mechanisms of woven carbon fiber and epoxy matrix composite laminates specifically engineered for marine environments. Utilizing an integrated methodological approach that combines standard fracture mechanics testing with high fidelity optical and acoustic monitoring, the study systematically tracks the initiation and steady state growth of cracks under controlled mechanical loading. The experimental setup is rigorously modified to simulate long term environmental degradation through accelerated synthetic seawater conditioning, revealing profound alterations in material toughness and microstructural failure modes. Advanced non contact measurement techniques, including Digital Image Correlation and Acoustic Emission monitoring, are deployed to capture localized strain fields and transient acoustic stress waves, providing a multi dimensional perspective on matrix cracking, fiber bridging, and interfacial debonding. The findings confirm that prolonged hygrothermal exposure significantly diminishes the fracture toughness of the composite laminates by plasticizing the polymer matrix and degrading the fiber to matrix interphase.