Abstract: A crack in a structural member introduces local flexibility that would affect vibration response of the structure. The presence of damage leads to changes in some of the lower natural frequencies and mode shapes. Damage detection is one of the important aspects in structural engineering for safety reasons. The traditional methods of damage detection include visual inspection or instrumental evaluation.Main problem is to detect existence of a crack together with its location and depth in the structural member.The presence of cracks causes changes in the physical properties of a structure which introducesflexibility, and thus reducing the stiffness of the structure with an inherent reduction in modal natural frequencies. Consequently it leads to the change in the dynamic response of the beam. In this paper, a model for free vibration analysis of a beam with an open edge crack has been presented. Variations of natural frequencies due to crack at various locations and with varying crack depths have been studied. A parametric study has been carried out. The cracked beams with different boundary conditions have been analyzed. The results obtained by FEA.

Keywords: Beam; Free vibration; Crack; Natural frequencies.