Prolonged Real Marine Environment Exposure of Composite Marine Structures

Abstract

As fiber reinforced polymer (FRP) composites become ever more established construction materials in the marine industry sector the influence of the harsh environmental operational conditions and its consequence on failure prediction of such structures is an imperative. Coupons of epoxy/glass and polyester/glass with various fiber layout configurations have been submerged under the sea for prolonged periods (6 and 12 months) in order to assess the impact on mechanical behavior of the material exposed to real marine environment as opposed to the more commonly adopted artificially produced laboratory sea environment and accelerated testing. Changes in mass, marine microbiology growth, tensile strength and morphological structures were analyzed after submersion and compared with samples exposed to room environment. All coupons have shown mass increase due to seawater absorption and microorganism growth in the organic resins matrices. The dynamic and level of change in tensile strength proved to be dependent on the fiber layout configuration. Optical and scanning electron microscopical investigation performed showed significant matrix morphological changes primarily due to salt crystal formation and the impact of sea microorganisms embedding in the resin. The collected experimental data will be used to develop a more realistic environmental input parameters for structural modeling of marine structures.