Structural Engineering and Mechanics

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Strengthening of capacity deficient RC beams - An experimental approach

  • Dar, M. Adil (Department of Civil Engineering, Indian Institute of Technology Delhi) ;
  • Subramanian, N. ;
  • Dar, A.R. (Department of Civil Engineering, National Institute of Technology Srinagar) ;
  • Rather, Amer Iliyas (Department of Civil Engineering, National Institute of Technology Srinagar) ;
  • Atif, Mir (Department of Civil Engineering, National Institute of Technology Srinagar) ;
  • Syed, Sayeeda (Department of Civil Engineering, National Institute of Technology Srinagar)
  • Received : 2018.10.26
  • Accepted : 2019.02.24
  • Published : 2019.05.10
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Abstract

Any revision of seismic codes usually demands a higher capacity from structural members, making existing structures unsafe particularly from strength considerations. Retrofitting of capacity deficient members is very suitable for tackling such situations. This paper presents an experimental study on different retrofitting measures adopted for strengthening a series of reinforced concrete (RC) beams. Four identical RC beam specimens were casted, out of which three specimens were strengthened by different schemes (viz., bolted hot rolled flat, bolted cold-formed steel channel, and carbon fibre reinforced polymer (CFRP) laminate, respectively) on their tension face and tested under four-point monotonic loading. This study focuses on the investigation of the flexural behaviour of these retrofitted beams, observed in terms of strength and stiffness. It was concluded that all retrofitting measures improved the structural performance of these beams. However, the cost involved with each strengthening mode was proportional to the improvement in the performance achieved.

Keywords

References

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