A Discussion of Differences Between Single-Lap Tests and Full-Scale Beam Tests in Terms of FRCM-Concrete Debonding

D'Antino T., Focacci F., Sneed L. H., Carloni C.

10th International Conference on Fibre-Reinforced Polymer (FRP) Composites in Civil Engineering (CICE), İstanbul, Turkey, 8 - 10 December 2021, vol.198, pp.609-620 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • Volume: 198
  • Doi Number: 10.1007/978-3-030-88166-5_52
  • City: İstanbul
  • Country: Turkey
  • Page Numbers: pp.609-620
  • Keywords: FRCM, Bond, Direct-shear tests, Full-scale beams, STRENGTHENING MATERIAL, BOND BEHAVIOR, COMPOSITES
  • Istanbul Technical University Affiliated: No


Fiber-reinforced cementitious matrix (FRCM) composites are a recent addition to the family of fiber-reinforced composites employed as externally-bonded reinforcement to strengthen reinforced concrete members. FRCM composites use a cementitious matrix rather than epoxy, which is typically used for the well-known fiber-reinforced polymer (FRP) composites. For both FRCM and FRP, the weakness of the technology is the premature debonding of the composites, which in most cases is a brittle phenomenon. The study of the debonding is often carried out at the small-scale level by employing small blocks of concrete with a strip of composite applied to one face. Different set-ups exist to study the phenomenon at the small scale. The most common set-up is the pull-push single-lap direct-shear test, in which the composite strip is pulled while the concrete block is restrained in such a way that the interfaces between the composite and the block is subjected mainly to shear stresses. The set-up is designed to represent the shear stress-transfer that occurs at the composite-concrete interface in full-scale strengthened beams.