Structural Performance of Concrete Columns Strengthened with Externally Bonded GFRP and Near Surface Mounted Steel

摘要

This paper presents an experimental study conducted to investigate the effects of strengthening using externally bonded GFRP confinement, Near Surface Mounted (NSM) technique and a combination of both on the behavior of circular concrete columns subjected to axial loading. Sixteen concrete columns were cast and classified into four groups. Group 1 includes plain concrete columns; Group 2 includes reinforced concrete columns with low transverse steel ratio; Group 3 includes ordinary reinforced concrete columns; Group 4 includes reinforced concrete columns with externally applied steel reinforcement (NSM). Beside control specimens, columns were strengthened using 2 layers of GFRP confining strips and (2 and 4) layers of GFRP confining jackets. Experimental test results showed significant improvements on the load carrying capacities of the tested columns. The best results achieved by using 4 layers of GFRP jackets.