Optimal lay-ups to maximize loss factor of cross-ply composite plate

The aim of the present work is to maximize loss factor of cross-ply composite sandwich plate simply supported on four edges by researching the ratio of different material parameters. To fulfill this purpose, based on the first-order shear deformation theory (FSDT), the governing equations are derived by employing the principle of Hamilton's principle and solved by means of the closed-form Navier method. Results show that bottom and top layer should have a symmetric arrangement; square plate or the similar should be the best choice, and viscoelastic thickness to total thickness ratio should take different values as the length to total thickness ratio (b/h) varies: the b/h value of less than 77.7 corresponding to hc/h value of 0.9; b/h value of 77.7-131.5 corresponding to hc/h value of 0.8; b/h value of 131.5-202.1 corresponding to hc/h value of 0.7; last, the range of b/h value is greater and greater, hc/h value corresponding to the maximum loss factor gradually tends to 0.5.