CLT Assumptions

• The plate is constructed of an arbitrary number of layers of orthotropic sheets bonded together. However, the orthotropic axes of material symmetry of an individual layer need not coincide with the x-y axes of the plate.
• The plate is thin, i.e., the thickness h is much smaller than the other physical dimensions.
• The displacements u , v , and w are small compared to the plate thickness.
• In-plane strains s x , s y and s xy are small compared to unity.
• In order to include in-plane force effects nonlinear terms in the equations of motion involving products of stresses and plate slopes are retained. All other nonlinear terms are neglected.

• Transverse shear strains s xz and s yz are negligible.
• Tangential displacements u and v are linear functions of the z coordinate.
• The transverse normal strain s z is negligible.
• Each ply obeys Hooke's law.
• The plate has constant thickness.
• Rotary inertia terms are negligible.
• There are no body forces.
• Transverse shear stresses s xz and s yz vanish on the surfaces z = h/2 .