Self-Compacting Fibre Reinforced Concrete (SCFRC) is a rather useful material in precast industry, leading to a significant reduction in construction time and costs, and possibly even labour shortages. SCFRC can be easily deployed in thin or irregularly shaped sections, such as thin-structures, where it may be very difficult to place conventional reinforcement. The addition of fibres enhances the behaviour of SCFRC structures at both serviceability limit state (durability, cracking, deformation) and ultimate limit state (bearing capacity and ductility), allowing in many cases to replace, totally or partially, the web reinforcement. However, even if several experiments available in literature showed that fibres, if provided in sufficient amount and with an adequate toughness, are significantly effective as shear reinforcement, just few of them focused on the shear behaviour of prestressed elements made of Self-Compacting Polypropylene Fibre Reinforced Concrete (SCPFRC). Polypropylene (PP) fibres, which ensure no corrosion problems, are now able to provide significant toughness and ductility to concrete. In this context, the present paper focuses on the use of PP fibres as shear reinforcement in double-tee SCPFRC prestressed members. Experimental results of full scale tests on six double-tee (DT) elements made in Self-Compacting Concrete (SCC) and SCPFRC are presented. Firstly, shear tests were conducts in areas where the prestressing is uniformly distributed, in order to evaluate the possibility of replacing the minimum amount of shear reinforcement by PP fibres. Moreover, several tests were also done at the end zones, which are more critical in shear as the beneficial effects of prestressing is not yet totally active (the prestressing force has still to be transferred from the tendons to concrete). Experimental results show that PP fibres can be used both to totally substitute the shear reinforcement required in zones with uniform prestressing, and to reduce the conventional reinforcement in end zones.
Comportamento a taglio di tegoli tipo "pigreco" in calcestruzzo autocompattante rinforzato con fibre in polipropilene
Conforti Antonio;Minelli Fausto
;Plizzari Giovanni;
2014-01-01
Abstract
Self-Compacting Fibre Reinforced Concrete (SCFRC) is a rather useful material in precast industry, leading to a significant reduction in construction time and costs, and possibly even labour shortages. SCFRC can be easily deployed in thin or irregularly shaped sections, such as thin-structures, where it may be very difficult to place conventional reinforcement. The addition of fibres enhances the behaviour of SCFRC structures at both serviceability limit state (durability, cracking, deformation) and ultimate limit state (bearing capacity and ductility), allowing in many cases to replace, totally or partially, the web reinforcement. However, even if several experiments available in literature showed that fibres, if provided in sufficient amount and with an adequate toughness, are significantly effective as shear reinforcement, just few of them focused on the shear behaviour of prestressed elements made of Self-Compacting Polypropylene Fibre Reinforced Concrete (SCPFRC). Polypropylene (PP) fibres, which ensure no corrosion problems, are now able to provide significant toughness and ductility to concrete. In this context, the present paper focuses on the use of PP fibres as shear reinforcement in double-tee SCPFRC prestressed members. Experimental results of full scale tests on six double-tee (DT) elements made in Self-Compacting Concrete (SCC) and SCPFRC are presented. Firstly, shear tests were conducts in areas where the prestressing is uniformly distributed, in order to evaluate the possibility of replacing the minimum amount of shear reinforcement by PP fibres. Moreover, several tests were also done at the end zones, which are more critical in shear as the beneficial effects of prestressing is not yet totally active (the prestressing force has still to be transferred from the tendons to concrete). Experimental results show that PP fibres can be used both to totally substitute the shear reinforcement required in zones with uniform prestressing, and to reduce the conventional reinforcement in end zones.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
