Surfaces in general can have many different sizes and shapes – from simple planes, such as walls, slabs or plates, to single-curved cylinders, such as silos, to multiple-curved membrane structures.
For structural analysis, surfaces are generated in the centroidal axis. By specifying the thickness and material, they get their stiffness. This allows you to determine the deformations and internal forces, which can then be designed according to the material and standard.