A SIMPLE 4-NODED COROTATIONAL SHELL ELEMENT FOR ARBITRARILY LARGE ROTATIONS

A simple four-noded geometrically nonlinear shell element, which handles arbitrarily large displacements and rotations, is presented in this paper. Based on the assumption of small incremental strain in each load step, a corotational procedure is employed to extract the pure deformational displacements and rotations and update element stresses and internal force vectors through a piece-wise linearized strain-displacement relation. To derive the tangent stiffness matrix, a three-dimensional degenerate, isoparametric shell model is employed. The 'locking' problem is alleviated by using mixed interpolation of tensorial transverse shear strain components. The approach described in this paper is ideally suited for implementation in existing linear finite element programs. A number of numerical examples are also presented.