  We present an isogeometric method for Kirchhoff-Love shell analysis of shell
structures with geometries composed of multiple patches and which possibly
possess extraordinary vertices, i.e. vertices with a valency different to four.
The proposed isogeometric shell discretisation is based on the one hand on the
approximation of the mid-surface by a particular class of multi-patch surfaces,
called analysis-suitable~$G^1$ [1], and on the other hand on the use of the
globally $C^1$-smooth isogeometric multi-patch spline space [2]. We use our
developed technique within an isogeometric Kirchhoff-Love shell formulation [3]
to study linear and non-linear shell problems on multi-patch structures.
Thereby, the numerical results show the great potential of our method for
efficient shell analysis of geometrically complex multi-patch structures which
cannot be modeled without the use of extraordinary vertices.
