Development of simple, robust finite elements based on refined theories for thick laminated beams

An approach for developing accurate, simple and robust two-noded C-0 finite elements based on shear deformable and layerwise (zig-zag) laminated beam theories is presented. First, a new generalized form of high-order shear deformation and zig-zag laminate theories is described that allows the continuity requirement on the transverse deflection degree freedom to be reduced. An associated finite element model is then developed that employs the penalty function concept in conjunction with an interdependent element interpolation scheme, making the element very accurate and robust for application to thick and thin laminated beams. The element stiffness coefficients are exactly integrated without giving rise to shear locking, and a consistent force vector is derived. Comparison of numerical results using the refined laminate models with exact elasticity solutions demonstrates that the current model is capable of accurately simulating the response of thin and moderately thick laminates, with or without damage.