Title: Laboratory Study of Flaw Detection in Concrete by the Pulse-Echo Method

Author(s): Nicholas J. Carino

Publication: Symposium Paper

Volume: 82

Issue:

Appears on pages(s): 557-580

Keywords: concretes; deterioration; hardened concretes; nondestructive tests; ultrasonic tests; voids.

DOI: 10.14359/6573

Date: 9/1/1984

Abstract:
study was performed to eva Iuate the applicability of Synopsis: using the echoes from mechanica I I y produced impact to Iocate hidden defects within concrete. The expected interactions of sphericaI waves with concrete-air interfaces are reviewed, and the results of experiments using artificial flaws in a large concrete s I ab are summarized. The foi lowing aspects were studied: type of impact source; distance from impact point to receiver; type of receiving transducer; depth of reflecting inter faces; and diffraction effects by sharp edges. The contact time of the impact is shown to be an important parameter for the success of the technique. The influence of the concrete thickness from impact point to the reflecting interface is an area of needed research.