Seismic performance evaluation of RC columns reinforced by GFRP composite sheets with clip connectors

This paper performs experimental and numerical studies on the seismic performance of non-seismically detailed RC columns retrofitted with the proposed GFRP strengthening device. The primary goal of this study was to improve the shear strength and ductility of weak-in-shear columns. It was proposed a strengthening device that was consisted of a prefabricated GFRP composite sheet and aluminum clip connectors. This device was designed to speed up the installation time and to minimize the disturbance to adjacent walls and non-structural components. Efficiency of the proposed GFRP strengthening installation is evaluated through a series of experiments on non-strengthened and strengthened 3:4 scale RC column specimens. Comparisons between experimental results of the non-strengthened and strengthened column specimens are conducted in terms of column strength, ultimate displacement ductility, amount of hysteretic dissipated energy, and column shear behavior. So, comparisons focused on ultimate displacement ductility and hysteretic dissipated energy. A series of finite element analyses are performed to confirm the efficiency of the proposed GFRP strengthening device.