A cross section defines the geometry of the shell in a plane parallel to the shell x-y plane. Through the section family of commands, you can describe the z direction of the element by defining consecutive layers. Each layer may vary in thickness, material type, orientation (from element x-axis), and number of integration points.

Alternatively, you can define homogeneous shell section behavior directly via preintegrated shell sections, a method commonly used in analyses involving laminated composite structures. With preintegrated shell sections, you can directly specify the membrane, bending, and coupling properties. The preintegrated method also enables analysis of complex geometry (with repeated patterns such as corrugated sheets) using equivalent shell section properties. For more information, see Creating a Preintegrated General Shell Section.