Abstract
A response reanalysis method based on a modal perturbation technique is applied to viscoelastically damped complex beam structures, viz., Gamma and F structures modified by free and constrained damping layer treatments. Variation of resonance frequency, which is the frequency at peak amplitude ratio, and the variation of the amplitude ratio are studied with the variation of coverage, and comparison is made with exact resonance frequencies and amplitude ratios using finite element analysis. The method is tested for convergence and evaluated from the point of view of computational effort involved in comparison with the exact method. (Author)