Types of structures

Définitiona) Trusses

Consist of slender elements, usually arranged in triangular fashion.

3D trusses
Plan trusses

Définitionb) Cables & Arches

Two other forms of structures used to span long distances are the cable and the arch. Cables are usually flexible and carry their loads in tension. Preferred than truss for span more than 150 ft (46 m). In contrast, the arch must be rigid and achieves its strength in compression.

Cables support their loads in tension
Arches support their loads in compression

Définitionc) Frames

Frames are often used in buildings and are composed of beams and columns that are either pin or fixed connected.

The loading on a frame causes bending of its member.

Frame members are subjected to internal axial, shear and moment loadings

Définitiond) Surface structures

A surface structure is made from a material having a very small thickness compared to its other dimensions. Sometimes this material is very flexible and can take the form of a tent or air-inflated structure. In both cases the material acts as a membrane that is subjected to pure tension.