Imaging of surface-braking concrete cracks using transient elastic waves

This study develops an imaging method to determine the depth and inclination of a surface-breaking crack in a concrete structure. The migration method in reflection seismology is adopted to process the surface response of the concrete structure recorded in a transient elastic wave test. An image is constructed that shows the location of the crack tip. The response curves are processed further by the quadratic interpolation method to determine the location of the crack tip. Then, a solid line is superposed on the image to represent the crack. Numerical examples are presented to illustrate the effectiveness of the proposed method to display cracks of various dip angles and lengths. Two model tests verify that this method can detect real cracks successfully. Copyright (C) 1996 Elsevier Science Ltd.