Damage in composite structures resulting from impact events is one of the most important aspects to be considered in the design and applications of composite materials. This research deals with fiber glass-epoxy-nanoclay laminate composites with 16 layers and 65% fiber volume fraction manufactured by vacuum assisted wet lay-up. To analyze how the composite overall vibrational behavior is affected by the nanoclay dispersion into the matrix, a set of nanocomposite with 0%, 1%, 2%, 5% and 10% wt were prepared. These plates were tested using Modal Analysis with one excitation point on a grid of 35 response measurement points. This procedure allows extracting the natural frequencies, the associated mode shapes and damping. The 5% nanoclay content laminates are the ones with better performance. For modes 1 and 7, where the bending-twisting shape mode is observed, the damping coefficient increases about 27%, in average. For modes 2 through 6, where bending is noticed, the average increase is around 68%, with peaks of 169%. A new shape mode comes out at 600 Hz frequency when the nanoclay content reaches 2%. Furthermore, the nanoclay presence, up to 10%, into fiber glass/epoxy laminates leads to a much higher improvement on damping coefficient (169%) than stiffness (21%).1 460473Luo, R.K., Green, E.R., Morrison, C.J., Impact damage analysis of composite plates (1999) Int J Impact Engng, 22 (5), pp. 435-447Naik, N.K., Shrirao, P., Composite structures under ballistic impact (2004) Composite Structures, 66 (8), pp. 578-590Avila, A.F., Soares, M.I., Silva Neto, A., An experimental investigation into NanoComposites under impact loadings (2005) Impact Loading of Lightweight Structures, pp. 89-102. , M. Alves and N. Jones, eds. 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