Detecting transverse material boundaries in multilayer anthropogenic structures

Abstract

The Kirchhoff approximation has been used to analytically determine the field that is generated by the reflection of an acoustic wave from an interface with a sharp acoustic impedance gradient. Visual formulas have been derived to describe the incoming signal when the boundary is exposed to a pulsed point source. On the basis of numerical modeling and an experimental study of multilayer systems, the suggested approach is applicable for detecting flaws in planar and cylindrical structures under pulse excitation. An algorithm is given for improving the accuracy of locating the rupture boundary. It is based on revealing correlations in wave field parameters at various points in the system.