Abstract:
For structural damage, the flexibility is more sensitive than its frequency or mode. The curvature difference matrix in flexibility is presented as a new index of nondestructive damage detection, derived from the change in structural flexibilities calculated before damaging and after damaging by means of difference calculation twice, firstly to columns, and then to rows. Therefore a new indicator called
61540;Flexibility Curvature Matrix Diagonal (
61540;
61472;FCMD) is constructed through principal diagonal elements based on the curvature difference matrix in flexibility. Numerical simulation examples indicate that the damage location and severity in structures, with single damage, multiple ones, lighter ones and ones at the supports, can be detected efficiently for cantilever beams, fixed supported beams, simply supported beams, continuous beams and so on by
61540;FCMD through only a few of the lower order modes. Compared to the aforementioned flexibility indicators and
61540;
61472;FCMD, such as the change in flexibility, the rate in flexibility, the curvature change in uniform load surface (ULSC), the effectiveness and advantage of
61540;
61472;FCMD, etc are shown.