Non-destructive testing of ultra high performance fibre reinforced concrete (UHPFRC): A feasibility study for using ultrasonic and resonant frequency testing techniques

The ultrasonic pulse velocity (UPV) and resonant frequency methods are two non-destructive testing techniques which have been used to measure the elastic properties of conventional concrete for many decades. This paper presents a study on these testing methods to determine the modulus of elasticity and Poisson’s ratio of ultra high performance fibre reinforced concrete (UHPFRC) containing 2% steel fibres by volume. Measurements were taken on slab and prism specimens using compression wave ultrasonic transducers and resonant frequency testing. Empirical relationships to determine the secant modulus of elasticity were studied. Results of the dynamic tests and empirical equations are compared to static tests and found to be in close agreement. This study found that ultrasonic wave propagation is the most reliable, easy and cost effective testing technique to use in the determination of the elastic properties of the UHPFRC mix used in this study.