Published in 1996
The objectives of this study were (1) to study the feasibility of using a pulsed, swept-frequency ultrasonic interferometer in the nondestructive evaluation of the degree of concrete consolidation and (2) to find a correlation between the degree of consolidation and the ultrasonic velocity calculated from the phase slope. The system developed incorporated a pulsed ultrasonic interferometer, an oscilloscope, and a PC for automatic data logging and processing. Typical results from the ultrasonic monitoring of consolidation in fresh concrete at an early age are presented, and a correlation between the degree of consolidation and the ultrasonic velocity calculated from the phase slope is shown. The system developed was able to make ultrasonic velocity, amplitude, waveform, and frequency measurements on plastic and hardened concrete. The results suggest that void size may affect ultrasonic travel in a manner that can be differentiated by the equipment. Variations in paste development that affect the measurement of velocity abate about 12 hr after mixing. Thereafter, the system can be an accurate approach for the nondestructive evaluation of the degree of concrete consolidation. The authors recommend additional study to further refine the capabilities of the system.
Last updated: December 17, 2023