Experimental Study on Friction Seismic Sway Bracings for Seismic Protection of Building Nonstructural Components

This study investigates seismic performance of a dry friction damper called Seismic Sway Bracing (SSB) used for seismic protection of nonstructural components (NSCs) such as mechanical and electrical lifeline systems in a building. Low- and high-performance type (L- and H-type) SSBs were experimentally tested from material-to-member-to-structure (or system) level. Firstly, six standard coupon tests of Q235 and SGC340 steel specimens were conducted. Then, tensile tests of 24 friction components of the damper (L- and H-components) were conducted. Finally, quasi-static tests of 20 specimens were conducted by installing single and double assemblies of friction dampers on the prefabricated rigid moment-resisting frame structure. Double assemblies of dampers were bridged by a pipe or a cable tray to accommodate additional weight. The damper's key influencing factors such as preloaded bolt's torque, ultimate bearing capacity, material validity, and fragility functions are investigated. Afterward, the best parameters for their optimum seismic performance are recommended. The result shows that these dry friction dampers are practical and reliable equipment to protect an NSC of a building from a horizontal swaying of an earthquake.