Identification of transverse crack location in flexural vibrations of free-free beams

This paper deals with the crack identification procedure for free-free uniform beams in flexural vibrations. The model of a transverse crack includes an equivalent linear spring, connecting two segments of a beam. By measuring the changes of natural frequencies in flexural vibrations it is possible to study the inverse problem-the crack site identification. The method is based on the assumption that the crack stiffness does not depend on the frequency of vibration. It requires at least two natural frequencies to be measured which are changed due to the crack existence. The comparison with the crack sites, identified by measuring both axial and flexural vibrations, showed better results for the flexural vibration case. (C) 1998 Academic Press Limited