Adaptive FEM for NURBS Surface Shells

The application of shell theories in the finite element method (FEM) requires a description of the shell midsurface geometry and its derivatives. Modern computer aided design software uses non-uniform rational B-splines (NURBS) for geometry description. We give some insights on how to implement adaptive FEM for NURBS surface Naghdi shells. A speciality is the incorporation of tangential vectors with continuous directions, but jumping lengths. Such vectors may occur when NURBS surfaces are combined. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)