Performance of FRP-Steel Joints and FRP-Steel Beams Fastened by FRP Anchors

This paper reports on the experimental results of utilizing anti-corrosive FRP anchors in FRP-steel joints and FRP-steel beams for strengthening purposes. The FRP anchors were introduced in replacement of the steel bolts typically used in the mechanical fastening methods of strengthening steel structures. FPR laminates were fastened to steel plates in a double-lap arrangement using 10 mm and 13 mm diameter FRP anchors without a bonding agent. The tested joints showed good bearing between the anchors and the fastened FRP laminates. FRP-steel joints fastened by the 10 mm diameter anchors experienced early shear fracture, risking the joints’ ductility. Better ultimate load capacity, bearing and ductility were attained by utilizing the 13 mm anchors compared to the 10 mm anchors. The fastening technique was then implemented on full-scale steel beams by fastening the FRP laminates to the beams’ bottom flange using the 13 mm FRP anchors. The flexural performance of the beams under two point loads was reported in view of the load-deflection curves, observed failure modes and strain measurements. The strengthened beams showed good bearing between the anchors and the laminates before the fracture of the anchors occurred. The strengthened beams showed higher ultimate load capacity than the un-strengthened beams, opening the horizon for additional investigations on the utilization of FRP anchors in strengthening steel beams.