ANALYSIS OF A ROTATING MULTILAYER ANNULAR PLATE MODELED VIA LAYERWISEZIGZAG THEORY - FREE-VIBRATION AND TRANSIENT ANALYSIS

The purpose of this work is to analyze the free vibration and transien t dynamic response of a rotating multi-layer annular plate. Layerwise zig-zag theory (LWZZ) based on the superposition of a global higher-or der shear deformation displacement field and a local linear zig-zag di splacement field (RHOT) is incorporated in the derivation of the gover ning equations of motion via Hamilton's principle. LWZZ automatically satisfies displacement continuity at the layer interfaces and by furth er application of stress continuity at the layer interfaces and tracti on free boundary conditions, the unknown degrees of freedom are reduce d to seven regardless of the number of layers. These are two in-plane displacements, two shear rotations, a transverse displacement and two section rotations. A four-node sector finite element in a cylindrical coordinate system is developed using RHOT. Two in-plane displacements and two shear rotations which are C-0 continuous are interpolated usin g bilinear functions and a transverse displacement and two section rot ations which are C-1 continuous are interpolated using higher-order he rmitian functions. Equivalent single layer theories (Kirchhoff-Love pl ate theory and Mindlin-Reissner plate theory) are also used to develop the finite elements. Comparison of numerical results using RHOT is ma de with equivalent single layer theories in various analyses. Free vib ration arid transient analysis are carried out to extract eigenvalues and corresponding eigenmodes and investigate the dynamic behavior of a multi-layer annular plate. (C) 1997 Published by Elsevier Science Ltd .