Effect of Moisture and Temperature of Cement Mortar Surfaces on Quality of Adhesive Bond

摘要

Carbon fiber reinforced plastics (CFRPs) are receiving greater utilization in many structural applications due to their excellent mechanical and corrosion resistance characteristics. In addition, they can be designed and fabricated to get adequate strength and stiffness by changing the angle and the sequence of their laminations. Applications in strengthening existing reinforced concrete beams, piles, and decks using carbon fiber sheets are also being pursued. Carbon fiber sheets are utilized to strengthen waterfront concrete structures such as wharves and piers. The sheets are bonded to the underside of reinforced concrete pier using structural adhesives. In this study, three structural adhesives, i.e., epoxy resin systems, were chosen to establish adhesive bonds to the hydraulic cement mortar cubes. The assemblies were subjected to the combinations of three different temperatures and four different relative humidities in an environmental control chamber. Effects of moisture and temperature on the quality of bonds were investigated using pull-off tests. Results are reported describing different types of failures observed.