Hybrid bonding system for optimizing structural performance of FRP flexurally strengthened concrete beams

J. G. Dai, H. Yokota, T. Ueda

Research output: Chapter in book / Conference proceedingConference article published in proceeding or bookAcademic researchpeer-review

2 Citations (Scopus)


This paper performed a test program on eighteen notched concrete beams flexurally strengthened with carbon fiber (CF) sheet. The objective was to improve the bonding configurations of FRP to concrete interface for achieving optimal flexural strengthening performance. Two types of sheet geometries (conventional CF sheet and new CF strand sheet) and three types of adhesive bonding systems (normal adhesive bonding, ductile adhesive bonding, and a hybrid use of two of them) were applied for these beams. Through combining the CF sheet geometry and adhesive bonding system in different ways, five bonding configurations were formulated as follows: (1) conventional CF sheet + normal adhesive bonding; (2) conventional CF sheet + ductile adhesive bonding; (3) CF strand sheet + normal adhesive bonding; (4) CF strand sheet + ductile adhesive bonding; and (5) CF sheet + hybrid (normal and ductile) adhesive bonding. Efficiencies of these various bonding configurations were compared in terms of the serviceability and ultimate state structural performance of the strengthened beams. The new type of CF strand sheet proved to be superior to conventional CF sheet. In addition, the hybrid adhesive bonding system demonstrated its advantage over normal and ductile adhesive bonding systems. Therefore, it was concluded that an ideal flexural strengthening design has been realized by optimizing the mechanical properties of bonding adhesives, bonding configurations, and CF sheet geometry.

Original languageEnglish
Title of host publicationProceedings of the 1st Asia-Pacific Conference on FRP in Structures, APFIS 2007
EditorsScott T. Smith
PublisherInternational Institute for FRP in Construction (IIFC)
Number of pages7
ISBN (Electronic)9789628014149
Publication statusPublished - 1 Jan 2007
Externally publishedYes
Event1st Asia-Pacific Conference on FRP in Structures, APFIS 2007 - Hong Kong, China
Duration: 12 Dec 200714 Dec 2007

Publication series

NameProceedings of the 1st Asia-Pacific Conference on FRP in Structures, APFIS 2007


Conference1st Asia-Pacific Conference on FRP in Structures, APFIS 2007
CityHong Kong


  • Carbon fiber sheet
  • Concrete beams
  • Ductile adhesive
  • Flexural strengthening
  • Hybrid bonding
  • Strand sheet

ASJC Scopus subject areas

  • Civil and Structural Engineering
  • Materials Science(all)

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