ABSTRACT
The analysis of shells from a purely computational point of view may be divided into: membrane analysis; analysis based on the interaction between membrane and flexural actions. For specific cases, e.g. spherical shells, hyperbolic paraboloids, under uniformly distributed loads, analytic solutions are available, and thus the straight application of the finite element method to membrane analysis has limited application. This chapter shows that problems arise with such membrane structure idealizations if flat sections occur such that the normal elastic stiffness at a node is zero. In general shell behaviour in which bending action occurs, it is possible to superpose the independent membrane and flexural (plate bending) behaviour with the appropriate spatial transformation to the global coordinate axes. Derivation of a completely general, doubly curved-shell element requires an analytic description of the shell geometry as well as high-order representation of the displacements.
