Strengthening of Reinforced Concrete Rectangular columns using Anchored CFRP Sheets

Abstract

This research presents an experimental and numerical investigation to study the behavior of reinforced concrete columns strengthened with carbon fiber polymers only and with anchored carbon fiber polymers under the effect of axial and eccentric compression loading with change in the spacing between CFRP sheets. The aim of this research is to study the effect of using CFRP anchors on the capacity of concentric and eccentric reinforced concrete columns. In order to achieve this goal, ten specimens of reinforced concrete columns divided into two sets were tested in the laboratory. The first set was tested under concentric load, while the other set was tested under eccentric load. Each set had one control sample, while the other four samples were wrapped with CFRP bands. Two of the wrapped samples were anchored and the others were not. The spacing between CFRP wraps was varied between 80 and 200 mm. The results showed that the concentric and eccentric capacity of the sample increased with decreasing the spacing between CFRP bands as long as the eccentricity is small enough to cause compression failure mode. But for the samples with tension failure which caused by large eccentricity, the CFRP bands have no effect on the capacity. It was also noted that the capacity of the anchored samples decreased from the un-anchored ones.