Theoretical assessment of the behaviour of cable bracing system with central steel cylinder

Different kinds of bracing systems are used as the basic methods for providing lateral stiffness and strength in building frames. In recent years, tension-only bracing systems have been suggested by researchers. Steel cable has been recognized as a flexible member which can tolerate tensional forces only. Using the tension-only members as bracing for structures has triggered the concept of applying cables as the lateral braces of structures. Despite the high stiffness and tensional strength of steel cables, they cannot be considered as proper devices in cross bracing due to their low ductility. One of the modern bracing systems is using cables along with a cylinder through which a pair of cables passes from their crossing point. Such bracing systems can be used in strengthening of moment-resisting frames. This research presents the equations that are related to the behavior of cable steel cylinder bracing. Also, the effects of cylinder dimensions and prestressing of cables on the behavior of the mentioned bracing were assessed. In such bracing with steel cylinder, both cables are under tension; therefore, the loosening of cables and their ability to cause impulses will be removed. Moreover, the cables reach their final strengths at higher frame lateral displacements. It is recommended to select the dimensions of the cylinder in such a way that the cables also reach their yielding limit in the damage limit displacement of the frame.