An experimental study of the shear behaviour of Ultra-High Performance Fibre Reinforced Concrete

Ultra-High Performance Concretes (UHPC) have shown great promise in recent years especially in mechanical performance, however, little attention has been paid to the shear friction behaviour of these materials. According to... [ view full abstract ]

Ultra-High Performance Concretes (UHPC) have shown great promise in recent years especially in mechanical performance, however, little attention has been paid to the shear friction behaviour of these materials. According to current design standards, there is a limit on the shear capacity of concrete related to a compressive strength limit. This limit resulted from research showing that increased compressive strength does not give the same increase in shear strength. This is not the case with Ultra-High Performance Fibre Reinforced Concrete (UHPFRC), as the fibre reinforcement can provide a higher shear capacity. The aim of this study is to investigate the shear behaviour of UHPC with different fibre contents and steel reinforcement ratios. Specimens with different amounts of steel fibres ranging from 0.55 % to 2.20 % by volume, and with different amounts of standard reinforcement were tested. The test results show that the shear failure of unreinforced UHPC is very brittle and sudden. Standard reinforcement has very little effect on the shear capacity of UHPC; however, fibre reinforcement significantly increases the shear capacity of UHPC.