Monitoring of the ultrasonic P-wave velocity in early-age concrete with embedded piezoelectric transducers

This note deals with the use of embedded piezoelectric transducers to monitor the ultrasonic P-wave velocity evolution during the setting and hardening phases of concrete subsequent to casting time. The main advantage of the technique is the possibility of overcoming the limitations of traditional methods which prevent the application of specific mechanical boundary conditions during the measurement. The embedded transducers are based on the smart aggregates concept previously developed at the University of Houston, Texas. Two piezoelectric transducers are embedded in a prismatic mold and the evolution of the P-wave velocity is recorded for the first 24h in concrete after the casting time. The results are very promising and show a good agreement with classical ultrasonic tests using external transducers. © 2012 IOP Publishing Ltd.