Study on the Influence of Material Inhomogeneity on Characteristics of Ultrasonic Wave Propagation

It is required to maintain the durability of concrete structures from the viewpoint of the proper control of maintenance. Thus, it is necessary to evaluate the soundness of the structures. The ultrasonic method which is one of nondestructive tests is tried to use as an evaluation method. In the case of the object of which density is high and its distribution is homogeneous, the ultrasonic can detect defects correctly. However, a concrete is inhomogeneous, and the wave spreads intricately if it comes to a crack or a discontinuous portion. Therefore, the limit and usefulness of applicability of the ultrasonic method are indefinite. In order to apply the ultrasonic method to concrete structures, it is necessary to grasp the influence of the properties of the concrete on the propagation of the wave. In this study, numerical analyses are conducted with considering the inhomogeneous of the concrete to check the applicability of the ultrasonic to the concrete.