Investigation of the effect of transverse crack on the modal properties of cantilever beams with different geometries using finite element analysis

Vibration analysis of structure for early detection of crack and its subsequent quantification for preventing sudden and unpredicted failure of the system and ensuring uninterrupted functionality, is one of the extensively used techniques that offer several advantages over others. The geometry of the structure plays an important role in governing its vibrational behavior in the presence of crack. The present work uses FEA to investigate the effect of single transverse crack on natural frequencies of vibration in cantilever beams of three different cross-sectional areas through Modal Analysis. The analysis has been carried out for two different crack depths with three different crack locations. The results reveal that the onset of crack reduces the natural frequency of vibration, although, the quite low sensitivity of frequency shift to damage, demands either a highly precise measurement or a considerably large damage to be confidently detected. Moreover, the effect of crack location on modal frequencies is not uniform for the beams, with varying cross-sections, however, for a particular mode, the shifts in frequency have a similar trend in all the beams.