Large Amplitude Vibration Analysis of Laminated Composite Spherical Panels Under Hygrothermal Environment.

Large amplitude vibration problem of laminated composite spherical shell panel under combined temperature and moisture environment is analyzed in this paper. A general nonlinear mathematical model of laminated composite panel is developed based on higher-order shear deformation theory (HSDT) by taking the geometric nonlinearity in the Green-Lagrange sense. The sets of nonlinear governing differential equations are obtained using Hamilton's principle and discretized via finite element steps. The nonlinear vibration responses are computed using a direct iterative method by incorporating hygral and/or temperature dependent material properties for laminated composite. The convergence behavior of the developed model has been checked and validated by comparing the responses with those available published results. Finally, some new examples are computed for different parameters (geometry, support condition and lamination scheme, etc.) and their effects on nonlinear free vibration responses under uneven environment are discussed. [ABSTRACT FROM AUTHOR]