| An outdoor exposure test and four accelerated tests for three types of pultruded GFRP, including painted specimens, were carried out and the changes in bending properties in a direction perpendicular to the pultruded direction were evaluated in this research. Unpainted specimens showed a slight reduction in the bending strength through the outdoor exposure test and it reached approximately 60% of the initial values, however, the bending modulus did not show any remarkable changes. There was no remarkable difference between the three types of GFRP; however, different types of matrix resins were used for each. Accelerated tests in moist air conditions without light irradiation for unpainted specimens showed a slight reduction in bending strength. This result suggests that moisture has an important influence on the reduction in mechanical properties. Accelerated tests in moist air with light irradiation for unpainted specimens showed a rapid reduction in bending strength from about 100 days of testing, compared with other conditions. This result suggests that light irradiation also has an influence on the reduction in mechanical properties of pultruded GFRP. Painted specimens showed no remarkable reduction in bending strength in every condition tested. This result suggests that top coatings play a protective role regarding the reduction in mechanical properties in deterioration tests. |
