In the present work, the possibilities of a CFRP-based strengthening technique, herein designated Core Drilled Mounted (CDM) technique, to increase the shear resistance of reinforced concrete elements were explored. For this purpose, an exploratory experimental program of short beam shear specimens was carefully carried out with the purpose of capturing the main features of the CFRP bar contribution for the concrete shear resistance. The adopted monitoring system was able of establishing a relationship between crack opening, crack sliding and strains in the CFRP strengthening bar, for each applied load. From the obtained results it was observed that a CFRP reinforcement ratio of 0,2% contributed for a 26% increment in terms of specimen shear resistance. Furthermore, at a crack width of 0,3 mm the strain level in the CFRP was enough significant to show that this is a promising technique for the shear and punching resistance of reinforced concrete structures. It was also observed that the contribution of the CFRP bars was more effective when concrete cohesive failure mode occurred, which indicates that bar-adhesive debond failure more should be avoided, which requires to select the most appropriate FRP-adhesive system.
Exploring the Possibilities of a New Technique for the Shear Strengthening of RC Elements
APRILE, Alessandra
2008
Abstract
In the present work, the possibilities of a CFRP-based strengthening technique, herein designated Core Drilled Mounted (CDM) technique, to increase the shear resistance of reinforced concrete elements were explored. For this purpose, an exploratory experimental program of short beam shear specimens was carefully carried out with the purpose of capturing the main features of the CFRP bar contribution for the concrete shear resistance. The adopted monitoring system was able of establishing a relationship between crack opening, crack sliding and strains in the CFRP strengthening bar, for each applied load. From the obtained results it was observed that a CFRP reinforcement ratio of 0,2% contributed for a 26% increment in terms of specimen shear resistance. Furthermore, at a crack width of 0,3 mm the strain level in the CFRP was enough significant to show that this is a promising technique for the shear and punching resistance of reinforced concrete structures. It was also observed that the contribution of the CFRP bars was more effective when concrete cohesive failure mode occurred, which indicates that bar-adhesive debond failure more should be avoided, which requires to select the most appropriate FRP-adhesive system.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
