Shear Strengthening of Reinforced Concrete Beam by Embedded Connector Steel Plate

Abstract

Many concrete structures fail to provide the specific needs due to change in the design standards, unexpected loading, corrosion, design and construction errors and due to random loading in the form of earthquakes. Damaged structures are to be replaced or retrofitted. Shear in the beam is primarily resisted by the stirrups provided as shear reinforcement. Beam members with insufficient stirrup bars require retrofitting in shear critical region, in order to enhance their shear strength. Different shear strengthening technique are provided using steel plates from this near surface mounted steel plate is one of them and the main drawback is debonding of the plate which is solved using embedded connector steel plate. The aim of this research is to investigate the shear resistance of reinforced concrete beam using embedded connector steel plates and to investigate the performances of shear-strengthened beams through numerical investigations. Shear strengthening of beams were done by providing additional embedded connector steel plate along the shear span of a beam using different connector depth and width of steel plate. A total of ten beams were modeled. All the beams have the same dimensions and reinforcement details. The beams were designed intentionally to fail in shear. The relative efficiency of the various strengthening steel plate width and connector depth were examined. The result of this research showed that the width of steel plate had great contribution on the shear strength by increasing the bond between concrete and plates. The connector depth also had a contribution by providing stiffness to the section. W30D200 had failure load increment 36.22% compared to control beam. The embedded connector of shear-strengthened beam of proposed design based on failure load (W30D200) had shown shear failure with higher failure load and maximum ductile nature. It was recommended that since strengthening using embedded steel plate is economical, resisted debonding of plates and had a positive effect on shear strengthening of concrete beam future studies should considered