弾性波法を適用したひび割れ深さの推定精度に関する実験的研究

Abstract

In this study, the elastic wave method was applied for estimating the crack depth, as the fundamental investigation to establish a new non-destructive testing method for concrete. In the experiments, the accuracies of depth estimations of the structural cracks occured by flexural loading and of the artificial crack with its width=1mm were compared to examine the applicability of the elastic wave method. Following results were obtained in this study : 1) The accuracy of depth estimation by the modified BS-method is relatively good for the artificial crack, but is unsufficient for the practical crack occured in the concrete structure (see Table 2). 2) The maximum amplitude and energy of measured waveform and frequency transfer function are very affected by the crack depth, even if the crack is the microcrack occured in the structure (see Figs. 4∿7).