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Retrofitting by adhesive bonding steel plates to the sides of R.C. beams. Part 2: Debonding of plates due to shear and design rules

  • Oehlers, Deric. J. (Department of Civil and Environmental Engineering, University of Adelaide) ;
  • Nguyen, Ninh T. (Department of Civil and Environmental Engineering, University of Adelaide) ;
  • Bradford, Mark A. (School of Civil Engineering, University of New South Wales)
  • Published : 2000.05.25

Abstract

A major cause of premature debonding of tension face plates is shear peeling (Jones et al. 1988, Swamy et al. 1989, Ziraba et al. 1994, Zhang et al. 1995), that is debonding at the plate ends that is associated with the formation of shear diagonal cracks that are caused by the action of vertical shear forces. It is shown in this paper how side plated beams are less prone to shear peeling than tension face plated beams, as the side plate automatically increases the resistance of the reinforced concrete beam to shear peeling. Tests are used to determine the increase in the shear peeling resistance that the side plates provide, and also the effect of vertical shear forces on the pure flexural peeling strength that was determined in the companion paper. Design rules are then developed to prevent premature debonding of the plate ends due to peeling and they are applied to the strengthening and stiffening of continuous reinforced concrete beams. It is shown how these design rules for side plated beams can be adapted to allow for propped and unpropped construction and the time effects of creep and shrinkage, and how side plates can be used in conjunction with tension face plates.

Keywords

References

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