Axial stress measurement method for hollow cylindrical steel structures based on non-dispersive characteristics of T (0,1) guided waves

This article presents an equivalent sound propagation model for hollow cylindrical structures subjected to axial stress, which yields theoretical solutions for sound velocity changes in steel pipes under varying stress levels. To enable the excitation and detection of T (0,1) mode guided waves in hollow steel pipes, an electromagnetic ultrasonic transducer (EMAT) array based on the principle of magnetostriction is designed and tested. To accurately extract nanosecond-level sound time changes due to stress, this study devises the LMS-Gabor algorithm, which exploits the non-dispersive properties of T (0,1) mode guided waves to process the echo signal. Experimental results demonstrate that this stress measurement approach can achieve high accuracy, even in the presence of noise and signals in the same frequency band.