Reliability considerations for 3D-shell elements

Publisher Summary This chapter formulates a 3D-shell finite element procedure well adapted to couple a shell with surrounding media, which improves the treatment of transverse strains, considering quadratic assumptions for displacements across the thickness. Like for general shell elements, the numerical locking is of particular concern for 3D-shell elements when bending dominated problems are analyzed. Moreover, the chapter identifies an additional source of locking—namely, the pinching strains. These elements can be made reliable by applying a specific treatment for each type of locking. In particular, it uses MITC9 techniques to process membrane and shear strains and interpolates the pinching strains at nodes to remedy the pinching locking. Numerical tests confirm that this treatment is effective and, indeed, a very satisfactory convergence behavior is observed for both types of fundamental asymptotic behavior.