Freeze-Thaw Resistance of Fiber-Reinforced Polymer Composites Adhesive Bonds with Underwater Curing Epoxy

摘要

A prefabricated fiber-reinforced polymer (FRP) composite shield or jacket was developed to repair wood piles in the field. Cylindrical E-glass/vinyl ester composite shells were bonded underwater to encase damaged wood piles. The resistance to freeze-thaw cycles of an underwater curing epoxy adhesive was evaluated. The standard test procedure for single-lap shear adhesion for FRP composite bonding, ASTM D5868, was selected. A standard procedure for freeze-thaw cycling exposure was adopted. The effect of freeze-thaw cycling exposure on the performance of the adhesive bond was discriminated by comparing the lap shear strength and the mode of failure of control and exposed samples. It was found that the lap shear strength is substantially reduced by exposure to freezing and thawing cycles. A change in the mode of failure from predominantly adhesive type to combined adhesive/cohesive type was noticed after exposure.