Development of aqua epoxy for repair and strengthening of RC structural members in underwater

Aqua epoxy is developed for repair and strengthening of structural members located underwater in this study. Among two types of aqua epoxy, one type is used as an adhesive between structure surface and retrofitting material, which is called aqua primer adhesive (APA). The other type is used for impregnating fiber reinforced polymer (FRP) sheets or reinforcing fibers, which is called aqua impregnation epoxy (AIE). To verify performance of APA and AIE and to obtain properties of the material, several tests such as pull-off strength test, bond shear strength test, and chemical resistance test, et cetera were carried out. The results showed that the developed aqua epoxies do not easily dissolve in wet conditions and do not create any residual particles during hardening. In spite of underwater conditions, it showed great workability and adhesion capacity, which are nearly equivalent to those used in dry conditions.