Abstract
Long-term durability of fiber-reinforced-plastics (FRP) under hostile environment is strongly influenced by the degradation of fiber strength. The degradation of the fiber strength has been quantified on the basis of microscopic stress corrosion cracking (SCC) of the initial defects on the fiber surface. In this paper, the fiber strength degradation in the single-fiber-composite (SFC) has been investigated under constant strain in water to represent the SCC of GFRP. By taking account of the fiber strain history, such as water absorption, thermal expansion, applied strain, the growth of the initial defect after the constant strain test was formulated. After the constant strain test, fragmentation test was conducted in order to estimate strength degradation of the embedded fiber. The remaining fiber strength distribution obtained from the fragmentation test was predicted using the model containing the Paris Law and the Arrhenius model presented by K. Liao.