Norimitsu Kishi, Ph.D., M.ASCE ; Masato Komuro, Ph.D. ; Tomoki Kawarai ; and Hiroshi Mikami, Ph.D



In this paper, which focuses on the fiber-reinforced polymer (FRP) sheet bonding method for improving the impact resistance of RC beams, low-velocity impact load tests are performed on RC beams strengthened with FRP sheets.

Both aramid FRP (AFRP) and carbon FRP (CFRP) sheets are used to experimentally investigate the flexural strengthening effect of the sheet materials. The impact force is created by dropping a 300-kg steel weight from various heights. The experiments are conducted using a single loading method for each beam, and the drop height of the weight is increased until the sheet debonded.

The results obtained from this study are as follows: the impact-resistance capacities of the beams are improved by flexural strengthening with FRP sheets; the strengthening effects of the sheets are similar, regardless of the sheet materials, when the axial stiffness values of the sheets are equal; and the maximum and residual deflections are approximately linearly distributed with increasing input impact energy until the FRP sheets debonded.