Abstract:

Recent interest in structural health of bridges and large buildings has lent new urgency to the development and enhancement of theories and methods in the field of nondestructive testing. We demonstrate a simple technique for acquiring data from an impact test using a basic electronic stethoscope. The continuous wavelet transform (CWT) is used to process and display the transient responses of a bolted joint in a structure with bolts installed in a properly tightened manner and bolts incorrectly installed. Results for tight and loose bolts are compared using the semblance analysis approach described by Cooper and Cowan [“Comparing time series using wavelet‐based semblance analysis,” Computers & Geosciences 34, 95–102 (2008)]. We enhance the interpretation of results using speaker‐driven audio output synthesized from CWT and semblance analysis.