It is known that the effect of a single crack in an axially vibrating rod causes the nodes of the mode shapes to move toward the crack. In this paper an investigation of the analogous problem for a beam in bending vibration is presented. The monotonicity property linking changes in node position and crack location does not hold in the bending case. The analysis of the direct problem, however, shows that the direction by which nodal points move may be useful for predicting damage location. Analytical results agree well with experimental tests performed on cracked steel beams.
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