Early-age compressive strength and dynamic modulus of FRC based on ultrasonic pulse velocity

Due to the increasing use of rapid construction methods and the challenges of maintaining construction schedules, a growing demand exists for procedures that can assure quality of work without sacrificing the pace of construction. The quality control of construction materials specifically, the mechanical properties of concrete are among the most important concerns in today’s construction industry. In the present study, the correlation between fiber-reinforced concrete’s compressive strength and dynamic modulus to its ultrasonic pulse velocity is investigated at early ages up to 7 days after mixing. An experimental program involving 189 FRC specimens were designed containing different types of structural fibers, fiber volume fractions, and water-to-cement ratios. Mathematical equations were developed to predict the early-age compressive strength and dynamic modulus of four different types of fiber-reinforced concrete based on ultrasonic pulse velocity. The predicted compressive strength and dynamic modulus from the proposed equations showed good agreement with the measured ones.