Ageing effect on the tensile behavior of pultruded CFRP rods

摘要

Pultruded rods of carbon fiber reinforced polymer (CFRP) are excellent alternative materials to steel tendons for the anchoring of deep-sea oil drilling floating platforms. However, the ageing of the rods for use as tension leg in platforms operating in harsh and unusual offshore conditions, and degradation mechanisms associated with these materials should be investigated. In this work, a systematic study was carried out aiming at evaluating how accelerated ageing affects the performance of pultruded CFRP rods, focusing on microstructure, tensile behavior, and thermal and chemical stability. CRFP rods with epoxy and with vinylester resins were evaluated. Rods were aged in hot distilled water, in hot seawater, and in UV radiation wheatherometer camera. Degradation was more severe in the vinyl-ester rods based on tensile strength and stiffness results. Deterioration of the fiber matrix interface and consequent fiber debonding was the main failure mechanism. The vinyl-ester rods presented higher water uptake than the epoxy rods in both distilled water and seawater, and lower mechanical strength after exposed in the latter. In general, the epoxy resin CFRP rods were more resistant to the ageing processes evaluated. (C) 2016 Elsevier Ltd. All rights reserved.