Force-based model for straight FRP anchors exhibiting fibre rupture failure mode

The use of Fibre Reinforced Polymer (FRP) materials as Externally Bonded Reinforcements (EBR) is an established technique for structural improvement of existing buildings. Nevertheless the technique features disadvantages, and premature FRP-to-concrete debonding has been commonly highlighted as one of the main problems, together with the difficulty to fully wrap the structural element when the structure presents complex geometries, FRP straight anchors are used to transfer the forces from the FRP sheet into the structural element, eliminating these two problems, but a comprehensive design method for FRP anchors has not yet been established despite the increased use and research on FRP anchors. An extensive experimental programme has been carried out as part of an on-going research project with the ultimate goal being the development of a design methodology to enable engineers to efficiently and reliably design FRP anchors. The influence of a number of parameters on the capacity of straight FRP anchors has been investigated in the research, but only the anchor size and the fanning angle of the fan portion are reported here. The model that defines the relationship between anchor size, fanning angle and the capacity of the anchor exhibiting fibre rupture is described.E. del Rey Castillo, M. Griffith and J. M. Ingha