Flexural strengthening of full-scale RC columns with Adhesively-bonded longitudinal CFRP plates: An experimental investigation

Conventional method of flexural strengthening of RC columns using carbon fiber reinforced poly-mer (CFRP) composites is transverse wrapping. However, for rectangular columns, this method is not effective or requires modification of column geometry. In this paper, a new configuration of rectangular RC column flexural strengthening system is investigated. The new system includes prefabricated CFRP plates vertically attached on column surfaces, and a short concrete jacket to prevent debonding of the CFRP composites. Five full-scale rectangular RC columns strengthened by either concrete jacket or vertical CFRP plates were tested under cyclic loading. Cyclic perfor-mance of the strengthened columns, and strain distribution of CFRP composites on the tension side were investigated. Test results showed that failure modes of rectangular RC columns were changed by application of CFRP composites. Vertical CFRP plates are effective in improving ulti-mate capacity and stiffness of rectangular RC columns under cyclic loading.