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Experimental Analysis of RC Elements Strengthened with CFRP Strips

This work is the result of experimental research conducted to determine the contribution of a composite material to improving the mechanical behavior of old, full-size reinforced T-beams in operation conditions under the action of short-term loads. The tension side of their ribs were strengthened by carbon strips of different lengths. Then, they were tested in loading by concentrated and uniformly distributed short-term loads. It was concluded that, for strengthening simply supported beams, there was no need for using CFRP strips longer than half of their length, and a lateral anchorage was not required. This refers to bending tests where no load increment exceeding 60% of the flexural strength is expected. The results obtained from this experiment may be of use in modern engineering practices, especially because tests conducted on old, full-size samples are very rare.

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Acknowledgments

The authors would like to express their gratitude to the Engineering Chamber of Montenegro for the financial support and to the local construction company “Fidija” for donation of the strengthening material needed for this research.

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Correspondence to N. K. Vuković.

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Russian translation published in Mekhanika Kompozitnykh Materialov, Vol. 56, No. 1, pp. 109-122, January-February, 2020.

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Vuković, N.K., Jevrić, M. & Zejak, R. Experimental Analysis of RC Elements Strengthened with CFRP Strips. Mech Compos Mater 56, 75–84 (2020). https://doi.org/10.1007/s11029-020-09861-x

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  • DOI: https://doi.org/10.1007/s11029-020-09861-x

Keywords

  • composite T-beams
  • full-size beams
  • CFRP strips
  • flexural behavior
  • experiment
  • short-term load