Improving stability and accuracy of Reissner-Mindlin plate finite elements via algebraic subgrid scale stabilization

Stabilized finite element methods for the solution of Reissner/Mindlin-type plate problems are presented. The formulations are based on previously described mixed formulations, like the assumed natural strain (ANS or MITC) concept or the discrete shear gap (DSG) method. In particular, the algebraic subgrid scale (ASGS) formulation is used for the stabilization term. The essential idea is to obtain stable elements and improve coarse mesh accuracy at the same time. It is shown how this can be achieved by a proper choice of stabilization parameters on the basis of physical insight into the mechanical behavior of shear deformable plates. In this context there is a strong relationship to concepts that have been developed long before stabilization techniques appeared in finite element technology, particularly the 'residual bending flexibility' or 'deflection matching' technique.