2-D analytical model for characterizing flexural damping responses of composite laminates

The flexural damping behaviors of composite laminates were characterized analytically in this study. A 2-D analytical model was developed based on the extension of Ni-Adams model [Ni RG, Adams RD. The damping and dynamic moduli of symmetric laminated composite beams-theoretical and experimental results. J Compos Mater 1984;18(2):104-21] accounting for the energy dissipation contributed by the laminar stresses of σ_xy and σ_yy. The specific damping capacity (SDC) of the composite was determined in accordance with the energy dissipation concept, which was defined as the ratio of the dissipated energy to the stored energy for per circle of vibration. The 2-D analytical model was validated by comparing the SDC of [0/-60/60]_s and [0/90/45/-45]_s laminates with the experimental data and the finite element (FEM) results. In addition, the effects of interlaminar stress on the flexural damping responses of laminated plates were also characterized in the 3-D FEM analysis. Results indicated that the interlaminar stress effect may not be so significant that the current 2-D model is adequate for the evaluation of the damping responses of the composite laminates. Furthermore, the present predictions, as compared to the Ni-Adams [Ni RG, Adams RD. The damping and dynamic moduli of symmetric laminated composite beams-theoretical and experimental results. J Compos Mater 1984;18(2):104-21] and Adams-Maheri [Adams RD, Maheri MR. Dynamic flexural properties of anisotropic fibrous composite beams. Compos Sci Technol 1994;50(4):497-514] models, generally demonstrate good agreements with the experimental data and the FEM results.