Experimental investigations of repair of pre-damaged steel-concrete composite beams using CFRP laminates and mechanical anchors: Fid-Bau Portal

Experimental investigations of repair of pre-damaged steel-concrete composite beams using CFRP laminates and mechanical anchors

Karam, Ehab C. / Hawileh, Rami A. / El Maaddawy, Tamer / Abdalla, Jamal A.

Abstract

AbstractThis paper investigates the flexural performance of pre-damaged steel-concrete composite beams repaired using externally-bonded carbon fiber-reinforced polymer (CFRP) laminates with and without mechanical anchors. A total of 10 beams were prepared, one beam was left undamaged, whereas nine beams were artificially damaged by cutting different U-shaped notches in the bottom flange at the beams’ mid-span that resulted in 45%, 73% and 100% losses in the flange thickness. Three damaged beams were not strengthened, whereas six damaged beams were repaired in flexure using externally-bonded CFRP laminates with and without mechanical anchors. The load-carrying capacities of the unstrengthened beams with damage states of 45%, 73% and 100% were approximately 11%, 23%, and 50% lower than that of the control-undamaged beam, respectively. The CFRP repair schemes were capable of restoring the original load capacity of the damaged beams with the lower damage state of 45%. For the beams with the higher damage states of 73% and 100%, the repair schemes could restore a maximum of 81% of the original load capacity. The inclusion of mechanical anchors in the repair regime improved the strength gain from 15% to 19% and from 46% to 63% for the beams with 45% and 100% damage states, respectively, relative to the strength of the corresponding damaged-unstrengthened beam.

Highlights•Study the flexural performance of pre-damaged steel-concrete composite beams.•Beams were repaired using externally-bonded CFRP laminates with and without mechanical.•Beams were artificially damaged by removing different flange thicknesses at midspan.•The CFRP repair scheme was capable of restoring the beams’ capacity.•The inclusion of mechanical anchors in the repair scheme improved the gain in strength.