Experimental Studies are carried out for the identification of the modal parameters and slao for the assessment of the damages of structures. Investigations are performed on simply supported beam structures with various degrees of damage. The modal parameters are estimated by the Extended Kalman Filtering Technique, and the parameters related to the structural damages evaluated by the Inverse Modal Perturbation Method. In order to improve the convergence of the Extended Kalman Filter algorithm, the Chebyshev Filter(Type II) is employed. From the results of the experimental studies, it has been found that the Extended Kalman Filtering Technique yields very good estimates, and the Chebyshev Filter(Type II) plays appropriately for overcoming the divergence problems as well as for improving the estimated results. From the damage assessment by the Inverse Modal Perturbation Method, it has been found that the location of damages are reasonably determined, but the estimates for the degrees of damage are not quite satisfactory. Further studies are suggested to improve the algorithm.
