Ultrasonic pulse velocity for determining the early age properties of dry-cast concrete containing ground granulated blast-furnace slag

This study evaluates the potential use of ultrasonic pulse velocity (UPV) for determining the early age compressive strength of dry-cast concrete containing varying percentages of ground granulated blast-furnace slag (GGBFS). The proposed approach includes computing the dynamic elastic modulus from UPV measurements, evaluating the static elastic modulus from experimentally measured dynamic-to-static elastic modulus ratios, and determining the compressive strength from the static elastic modulus using formulae suggested in ACI-363. The early age strengths of dry-cast concrete containing varying amount of GGBFS, which are determined using UPV measurements, are in good agreement with the measured strength. The evaluation is also extended to include five datasets reported in published literature for concrete containing varying types and amounts of mineral admixtures. Key words: concrete, compressive strength, dry cast, early age properties, ground granulated blast-furnace slag (GGBFS), ultrasonic pulse velocity (UPV).