Imaging defects in concrete structures using accumulated SIBIE

Images created by Stack Imaging Spectral amplitudes Based on the Impact-Echo (SIBIE) method are basically one-dimensional because a single frequency domain spectrum for waves reflected from a single point due to impact is used to create them. The method has a limitation for representing two-dimensional defects in a cross section of a concrete structural element. This study focused on defect detection and visualization in a concrete structural element using multiple impacts and accumulated SIBIE. An impactor was used to induce energy at multiple points positioned at prescribed intervals along the surface of a structure element. A modified SIBIE method was applied to the collected data at multiple points and the SIBIE images were accumulated to generate one image (an accumulated SIBIE image). As a result, the defect positions are successfully represented in the cross section of the structural element using a two-dimensional coordinate system.