Critical yielding length model for predicting mid-span debonding in FRP flexural strengthened RC beams

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

Abstract

Yielding of the internal steel reinforcement is an important mechanism that influences the mid-span debonding behavior in FRP flexural strengthened RC member since the FRP is required to carry additional forces beyond the condition of steel yielding. However, rational design practice dictates an appropriate limit state is defined when steel yielding is assured prior to FRP debonding. This paper proposes a criterion which correlates the occurrence of mid-span debonding to the formulation of a critical steel yielding length. Once this length is exceeded the average bond stress in the FRP/concrete interface exceeds its threshold value, which proves to correlate with the average bond resistance in a FRP/concrete joint under simple shear loading. This proposed mid-span debonding concept is based on traditional sections analysis which is conventionally applied in design practice. Hence complex bond stress-slip analyses are avoided. Furthermore, the proposed model incorporates not only the bond properties of FRP/concrete interface but also the beam geometry, and properties of steel and FRP reinforcement in the analysis of mid-span debonding strength. Based upon a solid database, the validity of the proposed simple mid-span debonding criterion is demonstrated.
Original languageEnglish
Title of host publicationProceedings of the 10th International Symposium on Structural Engineering for Young Experts, ISSEYE 2008
Pages1445-1450
Number of pages6
Publication statusPublished - 1 Dec 2008
Event10th International Symposium on Structural Engineering for Young Experts, ISSEYE 2008 - Changsha, China
Duration: 19 Oct 200821 Oct 2008

Conference

Conference10th International Symposium on Structural Engineering for Young Experts, ISSEYE 2008
Country/TerritoryChina
CityChangsha
Period19/10/0821/10/08

Keywords

  • Debonding
  • Flexural strengthening
  • FRP
  • Reinforced concrete beams

ASJC Scopus subject areas

  • Civil and Structural Engineering

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