Interaction forces in RC beams strengthened with NSM FRP round bars

S. S. Zhang, T. Yu

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

Abstract

The near-surface mounted (NSM) strengthening method has attracted an increasing worldwide attention in the last decade. Although the bond efficiency between FRP and concrete in the NSM method is much improved compared with the externally bonded (EB) FRP strengthening method, debonding failures have also been often observed in reinforced concrete (RC) beams strengthened with NSM FRP bars. In such FRP-strengthened RC beams, debonding may initiate at either of the two ends of the NSM bar (i.e. end debonding), due to the existence of large localized interaction forces between the NSM bar and concrete near the bar ends. This paper presents an analytical solution to the interaction forces in RC beams strengthened with NSM FRP round bars, which are one of the most popular types of FRP bars used for NSM strengthening. The key elements of the proposed analytical solution are the two interfacial stiffness parameters (i.e. tangential interfacial stiffness and normal interfacial stiffness) and the eccentricity of the tangential interaction force to the centroid of the NSM bar. The accuracy of the analytical solution is verified with predictions from a sophisticated 3D finite-element (FE) model of a RC beam strengthened with a NSM round bar.

Original languageEnglish
Title of host publicationProceedings of the 8th International Conference on Fibre-Reinforced Polymer (FRP) Composites in Civil Engineering, CICE 2016
EditorsJ.G. Dai, J.G. Teng
PublisherDepartment of Civil and Environmental Engineering and Research Institute for Sustainable Urban Development, The Hong Kong Polytechnic University
Pages955-959
Number of pages5
ISBN (Electronic)9789881448026
Publication statusPublished - 1 Jan 2016
Externally publishedYes
Event8th International Conference on Fibre-Reinforced Polymer (FRP) Composites in Civil Engineering, CICE 2016 - Hong Kong, China
Duration: 14 Dec 201616 Dec 2016

Publication series

NameProceedings of the 8th International Conference on Fibre-Reinforced Polymer (FRP) Composites in Civil Engineering, CICE 2016

Conference

Conference8th International Conference on Fibre-Reinforced Polymer (FRP) Composites in Civil Engineering, CICE 2016
CountryChina
CityHong Kong
Period14/12/1616/12/16

Keywords

  • Finite element (FE) analysis
  • FRP
  • Interaction forces
  • Interfacial stiffness
  • Near-surface mounted (NSM)
  • RC beams

ASJC Scopus subject areas

  • Civil and Structural Engineering
  • Polymers and Plastics

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