Characterisation of pultruded fibre-reinforced composites for use in aggressive environments

This research work focuses on the material characterisation of pultruded fibre reinforced composites for use in aggressive environments, including materials selection for physical properties, cost and durability. Consideration has been given to glass, carbon and aramid reinforcements, in conjunction with polyester, vinyl ester and hybrid resins. Interfacial strength, flexural strength and modulus were all investigated and characterised considering different levels of reinforcement up to a maximum of 85% by weight. On composite pultruded products water absorption deviated from 'Fickian behaviour' to an extent determined by temperature. The flexural strength, interlaminar shear strength (ILSS) and modulus measurements showed a strong dependence on moisture content, to a varying degree. With increasing reinforcement, flexural strength and modulus increased and the failure mechanism varied from compressive, to mixed compressive–tensile, to tensile, due to the environmental conditions. Conditioning of pultruded composite rebar in water illustrated that degradation occurs, accelerated by temperature. [Continues.]