Abstract: The maximum of each column of flexibility curvature matrix constructed from flexibility matrix is presented as a new indicator F_CM for damage detection.The numerical simulations indicate that the damage location in structures can be identified by F_CM for cantilever beams,fixed supported beams,simply supported beams,continuous beams and so on without baseline modal parameters.Not only simple damage but also multiple ones can be detected with satisfactory precision by F_CM using only a few of the lower frequency modes.