Flexural behavior of reinforced concrete beams strengthened with an ultra-high performance concrete panel of various thicknesses

  • Seonhyeok Kim (Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology) ;
  • Taegeon Kil (Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology) ;
  • Sangmin Shin (Korea Institute of Civil Engineering and Building Technology) ;
  • Daeik Jang (Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology) ;
  • H.N. Yoon (Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology) ;
  • Jin-Ho Bae (Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology) ;
  • Joonho Seo (Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology) ;
  • Beomjoo Yang (School of Civil Engineering, Chungbuk National University)
  • Received : 2022.11.07
  • Accepted : 2023.07.05
  • Published : 2023.11.25


The present study investigated the flexural behavior of reinforced concrete (RC) beams strengthened with an ultrahigh performance concrete (UHPC) panel having various thicknesses. Two fabrication methods were introduced in this study; one was the direct casting of UHPC onto the bottom surface of the RC beams (I-series), and the other was the attachment of a prefabricated UHPC panel using an adhesive (E-series). UHPC panels having thicknesses of 10, 30, 50, and 70 mm were applied to RC beams, and these specimens were subjected to four-point loading to assess the effect of the UHPC thickness on the flexural strengthening of RC beams. The test results indicated that the peak strength and initial stiffness were vastly enhanced with an increase in the thickness of the UHPC panel, showing an improved energy dissipation capacity. In particular, the peak strength of the E-series specimens was higher than that of I-series specimens, showing high compatibility between the RC beam and the UHPC panel. The experimental test results were comparatively explored with a discussion of numerical analysis. Numerical analysis results showed that the predictions are in fair agreement with experimental results.



This work was supported by the National Research Foundation of Korea grant funded by the Korean government (MSIT) (2020R1C1C1005063).


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