Zigzag Sublaminate Model for Nonlinear Analysis of Laminated Panels

A geometrically nonlinear first-order zigzag sublaminate theory and finite-element model are presented that account for moderately large displacements and moderate rotations using a total Lagrangian formulation. The model contains special laminated plate bending kinematics but is cast in the form of a 3D eight-noded brick finite-element topology with five engineering degrees of freedom per node-three translations and two rotations. This permits discretization through the thickness of a laminate to obtain higher accuracy of displacements and stresses when required. The accuracy of the present model is demonstrated by comparing its structural response predictions with results from previous experimental investigations and with numerical tests using a commercial finite-element code.