USING A DAMPER AND PRE-TENSIONED CABLES WITH DIFFERENT ARRANGEMENTS AND OPTIMIZED PATHS FOR A LATERAL RESISTANCE SYSTEM

Cable is known as a flexible element that can only undergo tension forces and has no compression strength. Using tension only elements within the bracing system of structures has formed the idea of using cables as part of a lateral bracing system.A pre-tensioned cable bracing system may be used to retrofit concrete buildings. A cable bracing system can be used as a continuous form, with and without sliding connections, similar to diagonal bracings. A cable system can also be used in a combined case; i.e. with and without sliding connections.In a continuous cable system, cables are passed through the stories by sliding connections and are anchored at the top or middle stories. In this case, the result of cable tension force at each adjacent story causes resistance against the frame lateral displacement, due to the change of cable elongation. A cable optimized form, in continuous cable and other systems, can be found by using different models.In this study, dynamic time history analysis was performed for two regular rising structures of short and moderate height. The structure was modeled as a concrete frame that was braced by a continuous cable or x-bracing cable. Models contained damper and no damper systems. Obtained results show a considerable decrease in displacements and, also, in the base shear of frames and force at the damper connection joint.In this paper, determining suitable cable arrangements, as well as cable path optimization for a continuous cable system, were investigated. Two mathematical equations were proposed to optimize the cable path. In order to optimize the cable path, drift was used as a parameter in this study.It was observed that using the damper at the end of cables is suitable, due to the following results obtained: the reduction of local effects at the connection of the cable and frame, due to high tension cable load; the prevention of cable slacking under environmental factors; less pre-tensioning force under structural vibration; and the reduction of base shear in comparison to the frame with no damper in the cables.