VIBRATION AND DAMPING ANALYSIS OF LAMINATED COMPOSITE AND SANDWICH SHELLS

Damping analysis under harmonic oscillations of a laminated composite and sandwich shells is performed. Finite-element modeling is based on the first-order shear deformation theory including rotation around the normal. The second-order isoparametric triangular finite-element noda l variables are three displacements and three rotations. A shear corre ction factor is introduced to account for the fact that the transverse shear distribution is not uniform through the shell thickness. A mode l of hysteretic damping is used to evaluate damping properties of the structure in harmonic oscillations. Damped frequencies of the shell ar e calculated by using the Lanczos method Modal damping of the structur e is calculated by using the energy method Numerical examples of dampi ng and vibration analysis of laminated composite and sandwich cylindri cal and conical shells are presented The numerical results are in good agreement with the reference solutions and experimental data.