AN ELASTIC-WAVE-BASED IMAGING METHOD FOR SCANNING THE DEFECTS INSIDE THE STRUCTURE

In this paper, a new nondestructive testing method utilizing elastic waves for imaging possible voids or defects in concrete structures is proposed. This method integrates the point-source/point receiver scheme with SAFT process to achieve the effect like scanning with a phase array system. This method is also equipped with large functioning depth because of the high energy feature that elastic waves usually possess over traditional ultrasound. Both numerical simulations and experimental tests were carried out to explore the capabilities of this method in revealing single or multiple defects implied in a matrix material. The results from numerical simulations indicate that this method can clearly reveal the number of the voids or defects and their locations and front-end profiles. Both the results from the numerical simulations and the experimental test indicate that this elastic-wave-based method exhibits high potential in inspecting the defects of in-situ concrete structures by imaging.