Dynamic response of functionally graded material shells with a discrete double directors shell element

The purpose of the paper is to compute the dynamic behavior of functionally graded material (FGM) shell structures subjected to time-varying excitation using 3D-shell model based on a discrete double directors shell element. The third-order shear deformation theory is introduced in the present method to remove the shear correction factor and improve the accuracy of transverse shear stresses. Material properties of the shell are assumed to be graded in the thickness direction by varying the volume fraction of the ceramic and the metallic constituents using general four-parameter power-law distribution. The transient excitation is defined in the time domain and known at each time. The damping material is neglected and the time derivative is approximated by Newmark method. Numerical results for deflection and stresses are presented for plates and spherical caps. The effect of an imposed force on the response of the FGM shell is discussed. The numerical examples prove a good accuracy and reliability compared to the few results available in literature.