Member properties are additional data not directly associated with the cross section, but as code check/design data. (buckling factors, restrained length, etc.)
It is important to know that any structural element defined must be always associated to a geometry entity and mesh parameters.
And it is essential not to confuse structural element with finite element. The former is the structural entity (defined as explained above) about to be meshed and the latter is actual mesh discretization of the structural entity. Following figure shows the difference between structural and finite element:
In the figure above a single shell structural element (slab) generates 32 finite elements (4-node shells) and each beam structural element (column) generates 7 finite linear elements (2-node beams).
Four fundamental types of structural elements can be defined: truss, beam, shell and solid structural elements.
Structural element
Geometry
Material
Beam
Curve (line, polyline…)
Structural/prestressing steel or concrete
Truss
Curve (line, polyline…)
Structural/prestressing steel or concrete
Shell
Surface
Structural steel or concrete
Solid 2D/3D
Surface/Volume
Any
Contact elements can be created between structural elements if needed.
After an element type or a combination of several element types for the analysis is selected, the necessary input data for the element(s) must be prepared. In general, the data consist of element connectivity, thickness for shell elements, cross section for beam elements, element coordinate system, etc.
