Linear static and dynamic analysis of laminated composite plates and shells using a 4-node quasi-conforming shell element

Quasi-conforming formulation of 4-node stress resultant shell element is presented for the linear static and dynamic analysis of composite plates and shells. The element formulations use interrelated displacement-rotation interpolations making it applicable for moderately thick and thin composite shells. The formulation also includes drilling degrees of freedom, allowing the modeling of stiffened composite plates and shells. The transverse shear stiffness is defined by an equilibrium approach instead of using the shear correction factor. The stiffness matrices for the present elements are explicitly expressed and the stresses are taken accurately at the nodal points. A lot of numerical tests were carried out for the validation of present 4-node composite shell element and the results are in good agreement with the references.