Ultrasonic Equipment at the IETcc

Abstract

A description is given of ultrasonic equipment developed at the I.E.T.c.c. (Instituto Eduardo Torroja de la Construcción y del Cemento) laboratory. This equipment is an addition to the facilities which the Metrology Department of the I.E.T.c.c. possessed, to undertake non destructive tests. The most significant features of this new equipment are: the possibility to work with varying frequencies (20 to 200 kc/sec); the use of both barium titanate and ferrite transducers; heterodyne auditive control of the marking frequency; and optional possibility of observing the incoming impulse both in the form of a damped high frequency wave, and as a low frequency, highly precise differentiated impulse. A revision of the theoretical basis involved in the impulse method has been carried out, and improvements have been also introduced in the more current applications in connection with mass and structural concrete, and even laboratory specimens. The revised method of testing has inherent limitations typical of these non destructive systems. These limitations have already been mentioned in earlier papers.