Simultaneous identification method of transmission point and physical properties (deterioration situation) in elastic wave tomography performed on measurement object of heterogeneous physical properties

摘要

PROBLEM TO BE SOLVED: To provide a transmission origin and physical property condition (deterioration condition) simultaneous identification method in elastic wave tomography, which can identify the transmission position or time required for tomographic analysis and can simultaneously identify physical property distribution condition (deterioration condition) even if physical properties of a measurement target are heterogeneous.SOLUTION: A method for nondestructive inspection of a measurement target comprises: receiving a sound generated by a measurement target; and performing analysis by obtaining estimated transmission time and position using a mathematical formula for estimating the transmission time and position based on the receipt time and position and a value of common propagation velocity that is set when the sound reaches a receipt waveform measurement sensor. In the method, if the target has heterogeneous physical properties, then, in an inspection region or suitably divided subregions, values of propagation velocity in accordance with physical properties are used in a mathematical formula to calculate, and operation to obtain estimated transmission time and position is repeatedly performed until becoming comparable with the receipt time, thereby identifying the transmission position and time of the sound and physical property distribution condition in the inspection region or subregions.