Effective Method of Repairing RC Beam Using Externally Bonded Steel Plate

Abstract:

Repair of reinforced concrete beam with externally bonded steel plate or fibre reinforced polymer (FRP) laminate is becoming both environmentally and economically preferable rather than replacement of deficient beam. The well known advantages of external reinforcement over other methods include; low cost, ease of maintenance and the ability to strengthen part of the structure while it is still in use. The disadvantage of this method, however, is the premature debonding of the externally bonded strips which is brittle and undesired mode of failure. It is also known that debonding of the externally bonded steel plates prevents the reinforced concrete (RC) beam from reaching its full strengthening capacity. The aim of this study was to increase the scientific understanding on the behaviour of damaged reinforced concrete beams strengthened and/or retrofitted for shear using vertical steel plate fixed with adhesive and steel connectors to eliminate or delay debonding failure. Four reinforced concrete beam specimens were prepared to investigate the effects of connectors in preventing or delaying premature debonding of shear strips to restore the capacities of fully damaged beams. Three damaged beams have been repaired and strengthened with steel plates and loaded monotonically up to the maximum load capacities in order to define load–deflection relationship. It is concluded that the repairing of severely shear-damaged RC beams with steel plates by using steel and adhesive connectors can fully restore the original shear capacities of the beams.

• Periodical: Applied Mechanics and Materials (Volume 567)
• Pages: 399-404
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.567.399
• Online since: June 2014
• Authors: Md Ashraful Alam*, Ali Sami Abdul Jabbar, Mohd Zamin Jumaat, Kamal Nasharuddin Mustapha
• Keywords: Connectors, Damaged Beam, Debonding, Repair for Shear, Steel Plate

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