Effects of Surface Preparation on the Performance of Reinforced Concrete Columns Retrofitted using RC Jacketing

Abstract

Retrofitting techniques become a very important structural strengthening method when we encounter variations in the design loading type due to client requirements, in case of poor construction practices due to the absence of skilled engineer’s supervision, when the owner wants vertical expansion above old construction or structural strengthening against seismic forces. In the developing world, the most widely used retrofitting technique is Reinforced concrete Jacketing and columns are the structural component that is mostly retrofitted against gravity loads. In this study, Physical modeling and testing were performed to enhance the axial strength and performance of the prevailing conventional technique of RC Jacketing. A new approach for RC Jacketing of square columns was introduced. For better performance, we tested the RC retrofitted technique with the surface being prepared (Removal of cover) of the base specimen and compared the axial strength of the specialized RC retrofitted column with the conventional RC Jacketed column and got 12% more axial strength for our surface prepared Retrofitted column.