In this paper, the free vibration analysis of cracked thin-walled channel section beam with warping effects has been studied for cantilever and simply supported beams using finite element method. A single edge crack is considered, which exists on the top flange and modeled as a line-spring element. The result shows that, when crack depth ratio increases, the non-dimensional natural frequency decreases. Besides that, the corresponding bending and torsional mode shapes for intact and cracked beams are taken into consideration to detect the crack location. It has been found that, the higher mode shapes are more sensitive to the crack depth ratio. Curvature damage factor (CDF) is found to be more useful in identification of the crack location with contribution of significant modes.

Keywords: Line spring model, Warping, Stress intensity factor, Modal parameter, Curvature damage factor.