Rapid scanning approaches for ultrasonic imaging of concrete: Fid-Bau Portal

Rapid scanning approaches for ultrasonic imaging of concrete

Schickert, M. / Tümmler, U. / Bühling, L.

Instruments and methods for ultrasonic imaging of concrete have been developed to a sufficient level. In contrast, the measurement process is too timeconsuming to encourage broad application. In particular, the coupling process makes scanning of plane apertures a tedious task. In this report, three coupling techniques and their respective application characteristics are discussed. With respect to the initial requirement for rapid scanning, no recommendation for a single method can be given from present experiences. Air coupling has the highest potential in terms of measurement speed, but the development of measurement arrangements is only in the early stages. Next in speed comes water coupling, with the proven ability to produce high-quality images. In practice, its use may sometimes be limited by its link to smooth concrete surfaces. Dry coupling seems to be the most universal technique. A wider range of surface qualities can be approached, and measurement speed is reasonably high. When it comes to cost effectiveness, none of these techniques at their present stage of development can compete with the Radar or impact-echo methods for simple thickness or detection measurements. On the other hand, ultrasound seems to have the highest potential for high resolution imaging and challenging measurement tasks. It could be concluded that further development should point in this direction.