Structural strengthening with FRPs is widely used in many engineering applications. In the field of Civil Engineering, composites are commonly bonded to extrados or intrados of beams. However, the application of this technique to constructions requires the satisfaction of a large number of requirements especially about the adhesive joining durabili ty and reliability. Thus, a proper description of mechanical behavior of the reinforcement interface and the prediction of debonding failure is necessary in order to realize a correct design phase of adhesively bonded structures. Within structural rehabilit ation with external bonded FRP systems, the debonding failure mode generall y occurs, due to dominant mode II fracture . In this work, mode II fracture behavior of concrete specimens, reinforced with pultruded FRP, has been experimentally investigated by the authors. Shear tests have been performed at the Structural Engineering Testing Hall of the University of Salerno by using both tradi tional equipment and non contact (Digital Image Correlation) technique. Starting from the experimental data, the experimental evaluati on of the J-integral and of specimens’ fracture toughness has been performed. Subsequently, by means of theoretical approach proposed by Rice, a cohesive law was associated to the J-integral and thus identified by comparison with experimental data. The proposed CZ model can be adopted in a Finite Element code for simulating the debonding phase in complex structures.
MODE II FRACTURE BEHAVIOUR OF ADHESIVELY BONDED REINFORCEMENTS
PERRELLA, MICHELE;BERARDI, Valentino Paolo;CRICRI', Gabriele
2017-01-01
Abstract
Structural strengthening with FRPs is widely used in many engineering applications. In the field of Civil Engineering, composites are commonly bonded to extrados or intrados of beams. However, the application of this technique to constructions requires the satisfaction of a large number of requirements especially about the adhesive joining durabili ty and reliability. Thus, a proper description of mechanical behavior of the reinforcement interface and the prediction of debonding failure is necessary in order to realize a correct design phase of adhesively bonded structures. Within structural rehabilit ation with external bonded FRP systems, the debonding failure mode generall y occurs, due to dominant mode II fracture . In this work, mode II fracture behavior of concrete specimens, reinforced with pultruded FRP, has been experimentally investigated by the authors. Shear tests have been performed at the Structural Engineering Testing Hall of the University of Salerno by using both tradi tional equipment and non contact (Digital Image Correlation) technique. Starting from the experimental data, the experimental evaluati on of the J-integral and of specimens’ fracture toughness has been performed. Subsequently, by means of theoretical approach proposed by Rice, a cohesive law was associated to the J-integral and thus identified by comparison with experimental data. The proposed CZ model can be adopted in a Finite Element code for simulating the debonding phase in complex structures.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
