FRP Wrapping of RC Structures Submitted to Seismic Loads

Abstract

An ongoing research project at the Université de Sherbrooke has shown that fiber reinforced polymers (FRPs) enhance ductility, flexural capacity and shear resistance of RC columns wrapped with such products. A recent experimental program was completed on 2.15-meter-height column specimens which were tested under combinations of axial and cyclic lateral loads. The initial objective of the experimental project was to test a variety of FRP wrapping configurations for reinforced-concrete bridge columns. The tested columns were subjected to cyclic lateral loads combined to sustained axial loads. The selected loads were representative of service conditions for bridges and building, respectively. Two wrapping configurations were selected for the columns: the first one was based on a “conventional” design method while the second one was the outcome of a displacement-based design procedure. Although the original intent of the research program was to develop applicable solutions for bridge piers submitted to seismic load conditions, the results can be useful for low-rise structures in general. The analysis presented in this chapter covers the following topics: (i) an evaluation of the extent of seismic-related damages in the retrofitted columns; (ii) a comparison of the resistance and ductility of columns before and after the FRP retrofit; and (iii) a comparison of the efficiency of two wrapping configurations. The main characteristics of the specimens, rehabilitation techniques, testing apparatus and a selection of result highlights are presented and discussed here.