Reflection Seismology for Nondestructive Evaluation

Providing reliable results in understandable form is challenging for ultrasonic nondestruc-tive evaluation. It is especially important to take into account the various parameters influ-encing the results. Our approach is unique in that (a) an array of ultrasonic receivers are used to reduce noise, (b) several kinds of filters are applied and (c) it provides geometrically correct images by migrating the data. The main objective of this study is to adopt and extend the capabilities of reflection seismology which is commonly used in the area of geophysical survey. Various parameters have been studied in an effort to reduce noise and improve accuracy. The noise reduction method by considering the effects of beam directivity are discussed. The techniques developed in this study have been investigated by both simulation and experimental studies for aluminum, mortar and concrete specimens. It has been shown that reflection seismology is feasible for small scale structures by considering the fundamental characteristics such as the dimension of wave sources and specimen