The MITC3 shell finite element enriched by interpolation covers

• We propose a scheme to enrich the MITC3 shell finite element by interpolation covers.
• The scheme increases the solution accuracy without any mesh refinement.
• The enriched MITC3 shell element shows good convergence behavior.
• The various numerical results demonstrate the feasibility and effectiveness.

In this paper, we develop a scheme to enrich the 3-node triangular MITC shell finite element by interpolation cover functions. The MITC method is used for the standard and enriched displacement interpolations. The enriched 3-node shell finite element not only captures higher gradients but also decreases inter-elemental stress jumps. In particular, the enrichment scheme increases the solution accuracy without any traditional local mesh refinement. Convergence studies considering a fully clamped square plate problem, cylindrical shell problems, and hyperboloid shell problems demonstrate the good predictive capability of the enriched MITC3 shell finite element, even when distorted meshes are used. We evaluate the effectiveness of the method, and also illustrate the use of the enrichment scheme applied only locally through the solution of two additional shell problems: a shaft–shaft interaction problem and a monster shell problem.