Water Absorption and Hygrothermal Ageing of Ultraviolet Cured Glass-Fiber Reinforced Acrylate Composites

摘要

In this article, an ultraviolet curable glass fiber reinforced polymer (UV-GFRP) composite developed for fast repair or strengthening of concrete structures, was investigated on its water absorption and hygrothermal ageing behaviors. Cured UV-GFRP coupons were subjected to immersion in distilled water or concrete pore solution (pH value around 13) for 4-8 months at room temperature and elevated temperatures (40 and 60 C), respectively. Water absorption and thermomechanical properties of the samples were tested as a function of immersion time. Water uptake curves of UV-GFRP exposed to elevated temperatures and/or alkaline solutions show serious mass loss. Debonding of fibers from resin matrix brought in increased coefficient of diffusion along fiber directions, due to the capillary effect. After 4 months of immersion in both media, the tensile strength of UV-GFRP was deteriorated remarkably, while the tensile modulus was less affected. According to Arrhenius equation, the tensile strength of UV-GFRP is predicted to remain 77.6% of its original value after 50 years when immersed in water at 20°C, but only 24.5% left in the case of alkaline solution. This suggests that the present UV-GFRP system does not suit for the application in strong alkaline environments.