Seismic retrofitting of RC columns with FRP jackets

The development and validation of a seismic retrofit system for reinforced concrete columns by continuous FRP jacktes is described. The column jacketing system consists of continuous FRP composite jacketes placed onto existing circular or rectangular concrete columns with variable jacket thickness along the column height based on experimentally validated design models. Jacket design criteria for various seismic failure modes of columns with circular and rectangular column geometry are described. The FRP jacket designs were validated through large scale bridge column model tests and were found to be just as effective as steel shell jacketing in providing desired inelastic design deformation capacity levels. An over-view of the developed design approaches and experimental validation results are presented.