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G.2 Types of Structures

A STRUCTURE can be defined as an assemblage of elements. STAAD.Pro is capable of analyzing and designing structures consisting of frame, plate/shell, and solid elements. Almost any type of structure can be analyzed by STAAD.Pro.

A3D framed structure with loads applied in any plane. This structure type is the most general.
This structure type is bound by a global X-Y coordinate system with loads in the same plane.
This structure type consists of truss members which can have only axial member forces and no bending in the members.
A 2D or 3D structure having no horizontal (global X or Z) movement of the structure [FX, FZ, and MY are restrained at every joint]. The floor framing (in global X-Z plane) of a building is an ideal example of a this type of structure. Columns can also be modeled with the floor in a FLOOR structure as long as the structure has no horizontal loading. If there is any horizontal load, it must be analyzed as a SPACE structure.

Specification of the correct structure type reduces the number of equations to be solved during the analysis. This results in a faster and more economic solution for the user. The degrees of freedom associated with frame elements of different types of structures is illustrated in the following figure.

Degrees of freedom in each type of Structure