Steel-free hybrid reinforcing bars for concrete structures

Jin Guang Teng, Bing Zhang, Shishun Zhang, Bing Fu

Research output: Journal article publicationJournal articleAcademic researchpeer-review

5 Citations (Scopus)


Extensive research has been conducted on the replacement of steel rebars with fibre-reinforced polymer rebars to eliminate the steel corrosion problem in conventional steel bar–reinforced concrete structures. However, as the performance of fibre-reinforced polymer rebars is substantially inferior in compression (due to issues such as fibre micro-buckling) than in tension, their use in concrete columns is generally not recommended; this poses a significant challenge when a steel-free structure is needed. This article presents a novel steel-free hybrid rebar developed at The Hong Kong Polytechnic University that overcomes the above-mentioned problem. Such a hybrid rebar typically consists of a central fibre-reinforced polymer rebar, an external fibre-reinforced polymer confining tube and an annular layer of high-strength cementitious material such as ultrahigh-performance concrete. To demonstrate the performance of these hybrid rebars, results from a series of preliminary tests and associated modelling work are presented in the article. These results indicate that (1) the fibre-reinforced polymer rebar at the centre is well supported against bar buckling and fibre micro-buckling, (2) the compressive strength of the fibre-reinforced polymer material can be fully mobilized and (3) the stress–strain response of hybrid rebars can be designed to resemble an elastic–plastic response with some post-yielding hardening.

Original languageEnglish
Pages (from-to)2617-2622
Number of pages6
JournalAdvances in Structural Engineering
Issue number16
Publication statusPublished - 1 Dec 2018


  • confinement
  • fibre-reinforced polymer
  • hybrid rebar
  • steel-free rebar
  • ultrahigh-performance concrete

ASJC Scopus subject areas

  • Civil and Structural Engineering
  • Building and Construction

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