Failure modes in filled hole GFRP laminates for connections between FRP and concrete

Abstract

The PERFOFRP connector consists on a perforated glass fibre reinforce polymer (GFRP) rib that is specially designed to perform the connection between thin concrete layers, which can be also useful in the context of structural rehabilitation. It stays embedded in the concrete layers, avoiding the use of complementary connecting techniques, like special gluing or bolting. This type of connection is similar to the Perfobond steel connectors proposed for steel and concrete composites structures. Perfobond shear connector failure depends on the concrete dowels load capacity, since the steel connector failure does not occur in ribs with adequate thickness. However, in the case of the PERFOFRP connectors, the load capacity can be limited by the failure of the connector itself. To achieve a better understanding on the behaviour of the GFRP connector, an experimental study, based on tests with perforated GFRP laminates submitted to pin-bearing tests, is carried out. The tests are performed with four different rectangular GFRP plates containing a circular hole of 30 mm diameter, and differing from each other in terms of stacking and amount of fibre plies. Two different geometries of specimens are studied to enhance the evaluation of two expected failure modes. Finally, the failure modes, the peak loads and the evolution of strain in the vicinity of the holes are presented and discussed.