Metrological Perspective of Ultrasonic Pulse Velocity Measurement Technique

The nondestructive testing of concrete structures by the measurement of Ultrasonic Pulse Velocity (UPV) is well known and widely used. Concrete is highly porous and attenuating material. Therefore, low-frequency ultrasonic propagation below 200 kHz is preferred for UPV measurement. UPV is estimated by accurately, measuring the transit time and sample travel path. Consequently, the accuracy of UPV estimation is affected by transit time measurement. Transit time is measured using either the counter method or the analog data acquisition method, both of which have different sources of errors. The counter method involves two sources of errors: crystal accuracy and threshold voltage comparison. Similarly, the data acquisition method also encompasses two sources of error: sampling rate and errors due to amplitude resolution of the analog-to-digital converter. This article is related to the analysis of errors and their degree of impact on the UPV measurement.