摘要： In civil engineering, imaging can be a useful non-destructive testing (NDT) tool for revealing defects in a concrete structure. To date, there is no effective method for imaging the defects inside in situ concrete structures. In this study, a new elastic wave-based NDT method has been developed and then applied to reveal the defects inside concrete specimens using an imaging method. This method integrates the point-source/point-receiver method with the synthetic aperture focusing technique (SAFT) to achieve a scanning effect when using a phase array system. This method operates with a large functioning depth because the transient elastic wave method possesses a high-energy feature, whereas the traditional ultrasonic method does not. As an alternative to using displacement responses, this method uses velocity responses to construct the SAFT image. Based on the numerical simulation and the experimental results, using the proposed method allowed a high image quality to be produced and successfully revealed defects underneath a layer of rebars. The results of this study indicate the great potential for using the elastic wave-based imaging method to inspect defects in situ concrete structures. 出版者： Taylor & Francis 出版日期： 2015-07-04 出處： Journal of the Chinese Institute of Engineers, 2015-07, Vol.38 (5), p.636-644 版權： 2015 The Chinese Institute of Engineers 2015 識別號： ISSN: 0253-3839 識別號： EISSN: 2158-7299 識別號： DOI: 10.1080/02533839.2015.1005025
