Bond behaviour of reinforcing bars in UHPFRC

This paper deals with the experimental determination of the bond behaviour between ultra-high performance fiber-reinforced concrete (UHPFRC) and reinforcing bars (rebars). An experimental campaign has been carried out to assess the bond behaviour considering different rebar diameters, different embedment lengths and different concrete covers. A relationship between bond strength, compressive strength and rebar diameter has been drawn from the results of this campaign and results found in the literature. Thanks to an original instrumentation method using Fiber-Optic Sensor, the local constitutive law linking the local relative displacement between UHPFRC and rebar and the bond stress has been determined and compared with the law proposed by fib Model Code 2010.