Shear Strengthening of Reinforced Concrete Columns Using Ferrocement Jacket

Abstract

This paper describes the results of a research effort on the strengthening, by use of circular ferrocement jackets (CFJs), of square reinforced concrete (RC) columns susceptible to shear failure. Based on 1:6 scale models, 6 identical RC columns were fabricated. Two of these columns were tested under as-built conditions; the other 4 were strengthened with different numbers of layers of wire mesh before being tested. Unless failure occurred at an earlier stage, all columns were tested under cyclic lateral forces and constant axial load. From test results, it was observed that both original columns suffered shear failure at low displacement ductility. By providing CFJs over the entire length, however, the displacement ductility of the columns could be improved greatly. A method to strengthen the design of columns with inadequate shear strength by using CFJs is also proposed.