Numerical framework for assessing the reusability of polymer laminates in marine environments under static loading

This study outlines a numerical framework for assessing the reusability of glass fibre-reinforced polymer laminates exposed to marine environments. The proposed approach integrates Fick’s law to model moisture diffusion, Puck’s failure criteria to predict fibre-dominated and matrix-dominated failure modes, and the element weakening method to simulate progressive material degradation. Experimental validation was conducted using specimens previously subjected to fatigue loading. Seven groups of reused specimens were created: one without aqueous diffusion during reuse and six with varying levels of seawater-induced damage considering two exposure times (70 and 300 days) and three permeability conditions controlled by applying coatings to selected surfaces of the specimens. The proposed numerical framework provided good predictions of ultimate tensile strength and contributed to understanding the mechanical behaviour of the tested composite material, proving to be suitable for assessing the reusability of polymer composite laminates. While the ultimate tensile strength did not decrease significantly with additional seawater damage, the changes in Young’s modulus were pronounced, emphasising the need for careful consideration in extended-use applications. In this context, incorporating surface coatings can mitigate the degradation induced by seawater exposure and improve the overall mechanical performance and longevity.