Ultrasonic Pulse Velocity Test on Hybrid Fiber Reinforced Concrete

Abstract

Concrete is a material of high importance in infrastructure and development projects. Concrete is characterized as a brittle material. In order to minimise the brittle failure, it is beneficial to add the fibers to the concrete mix without compromising the quality of concrete. The length of polypropylene fibers (PPF) and steel fiber (SF) used in concrete mixtures are 50mmand 35mmrespectively. The aimof this paper is to learn the quality of concrete and dynamic modulus of elasticity by using Ultrasonic Pulse Velocity (UPV). The percentages of polypropylene fiber are 0%, 0.3%, 0.6%, 0.7%, 1% and steel fiber are 0%, 0.1%, 0.4%, 0.7%, 1%. Comparison of conventional and Hybrid fiber-reinforced concrete (HFRC) is studied further. Experimental investigation is carried out on 18 cubes of M40 grade concrete of size 150X150X150mm for Ultrasonic Pulse Velocity (UPV) and compression test. The results show that conventional as well as fiberreinforced concrete are of excellent and of good quality with 28-day strength of 60.74 MPa. Conventional concrete has the highest pulse velocity and dynamic modulus of elasticity of 5.1903 5Øß5Ø‘Ü and 62.43 GPa. Next to it C-3-5 has a pulse velocity of 4.886 5Øß5Ø‘Ü, dynamic modulus of elasticity as 48.61 GPa and compressive strength of 61.77 MPa. Among FRCs Polypropylene fiber-reinforced concrete with 1% fiber volume fraction showed appreciable value of pulse velocity and elasticmodulus. In hybrid fiber-reinforced concrete C-3-3with 0.7%SF and 0.3% PPF has proven to have better quality as compared with other HFRCs.