Effect of types of aggregate and sand-to-aggregate volume ratio on UPV in concrete

An experimental investigation was carried out to understand the variation of ultrasonic pulse velocity (UPV) in concrete with the types of coarse aggregate and sand-to-aggregate volume ratio (s/a). The types of aggregate investigated were brick chips, crushed stone, round shaped stone and black stone. Sand-to-aggregate ratios were 0.36, 0.40, and 0.44 and W/C ratios were 0.45, 0.50, and 0.55. Concrete specimens were made and tested for UPV, compressive strength, and modulus of elasticity. UPV in concrete is significantly influenced by the types of aggregate and s/a ratio in addition to the compressive strength of concrete. UPV in concrete is reduced with the increase of s/a ratio. Relationships between UPV and compressive strength, and UPV and modulus of elasticity are proposed for aggregates investigated.