Moment-curvature based modelling of FRPstrengthened RC members anchored with FRP anchors

Abstract

Debonding of externally bonded fibre-reinforced polymer (FRP) composites in FRP-concrete bonded interfaces occurs in generally a brittle manner and at a level of strain well below the strain capacity of the FRP. The addition of anchorage devices can, however, enhance the strain capacity and deformability of the bonded interface. The proof of concept has been demonstrated in experimental studies over the years although there is much less development of modelling methods by comparison that address the full-range of response from initial loading to eventual interface and anchorage failure. This paper presents the details of a closed-form analytical model that enables the complete load-deflection response of FRP flexurally-strengthened RC members that contain anchorage devices to be generated. The method relies upon establishing predefined moment-curvature expressions corresponding to key stages of the member behaviour.