Modelling damage evolution of carbon fiber-reinforced epoxy polymer composites in seawater sea sand concrete environment

The paper aims to study the damage mechanism and damage evolution of carbon fiber-reinforced epoxy polymer (CFRP) composites under seawater sea sand concrete (SWSSC) environment in coastal, marine and ocean engineering. CFRP composites were exposed into the simulated SWSSC solution to carry out the accelerated corrosion experiment at 25 degrees C, 40 degrees C and 55 degrees C, respectively. The degradation mechanism was revealed using scanning electrical microscope, X-ray microscope and Fourier transform infrared spectroscopy. The damage of CFRP composites is mainly induced by the hydrolysis of cured epoxy resin, and this process is accelerated in alkaline environment because the hydroxyl ions can react with the carboxylic acid resulting from hydrolyzation. Two approaches, chemical etching rate-based method and hydroxyl ions diffusion-based method, have been proposed. Their corresponding finite element models have been developed to predict the degradation of CFRP bars. The fidelity of the two approaches has been validated by comparing the predicted results with the test data.

Automated summary

This paper investigates the damage mechanism and evolution of CFRP composites in SWSSC environment, revealing that the damage is mainly induced by the hydrolysis of cured epoxy resin accelerated in alkaline conditions. Two methods for predicting CFRP degradation were proposed and validated by comparing with test data.