Structural Health Monitoring Techniques for Detecting Incipient Buckling

摘要

Among different failure modes observed in structures, loss of stability due to buckling is a major concern. Buckling may be induced because of overload or as a consequence of other types of failures in the structure. This paper examines two techniques, namely, vibration based analysis, and stress wave propagation analysis for detecting this onset of instability. The responses of a bar and a plate are used to illustrate the effectiveness of the two approaches. These analyses were performed through finite element simulations and limited experiments. Changes in vibration frequencies and mode shapes are found to provide good indications of the impending failure as well as its progress. Changes in the wave propagation characteristics showed some limited success in detecting the incipient buckling.