Shear Capacity of Reinforced Concrete Beam with an Opening Retrofit Using Steel Fiber and Metakaolin

Abstract

The presence of opening in the shear zone of beams can significantly affect the load-carrying capacity and the shear resistance of the beams. Previous research hasshown that strengthening provides promising results in increasing the performance of the beams with opening. Therefore, this studypresentsthe experimental work of five (5) reinforced concrete beam with opening at shear zone,added with steel fibre and metakaolin to increase the shear capacity of the beam. All beams were cast and tested under four-point bending test. One beam served as the control specimen, two beams hadone and twoopening respectively while the other two beams also had one and two opening butwith added steel fibre and metakaolin. The type of steel fibre used was a hooked-end steel fiberwith the dimensions of 0.9mm in diameter, 60mm in length.0.5% of steel fiber wasadded by volume of beam, and 5% of metakaolin by volume of beamwere used. From the experimental results, it was found that the two beams with added steel fibre and metakaolin shows an increase in shear capacity compared with the beams with opening without the steel fibre and metakaolin. The highest shear force recorded was 79.11 kN (beams with added steel fibre and metakaolin) which showedan increase ofabout 54.3 % compared with the same beam with opening without added steel fibre and metakaolin.