cable structuresStructural steel cable is a non-rigid, rope-like material that is flexible and shapeless in its natural state. A brick bearing wall or concrete frame stands on its own accord before supporting the weight of a building but structural steel wire cable is unique in that it is completely reliant on its load to achieve its form.Cable sizes can range from one eighth of an inch to 3 or 4 feet in diameter, and whether used for the guardrails of a stair or the catenary of a bridge, cable structures are unique in that they retain their essence as tensile constructions. Because of their structural configuration, cables are quite often on the exterior of the building and thus are not subject to the same fire protection ratings that interior structural members are.materials:Steel, nylon ropes or plasticized cables may be used for different structures. Steel Cables : The high tensile strength of steel combined with the efficiency of simple tension, makes a steel cable the ideal structural element to span large distances. Nylon and plastics are suitable only for temporary structures, spanning small distances.other structural members like masts, compression rings, arches or beams and compression struts may be of concrete or steel preferably. Struts may also be of timber. Suspension Cables, because of their being stressed only by simple tension with regard to weight/span are the most economical system of spanning space.