Nonlinear dynamics of shells using an invariant-based triangular shell element

It is proposed to use a curvilinear triangular finite element with a small number of degrees of freedom to reduce the amount of calculations in solving problems of the numerical nonlinear dynamics of shells using step-by-step integration over time. The compactness of the finite-element formulation is achieved by applying strain-tensor invariants. This is done using natural deformation components which are determined in the directions of three coordinate lines parallel to the sides of the element. Solutions describing large displacements, rotation angles, and buckling dynamics are given to analyze the capabilities of the proposed finite-element model.