Seismic performance evaluation of exterior StrongBack braces in high-rise structures

Earthquakes pose significant risks to infrastructure, often leading to substantial economic losses and human casualties due to structural failures. One of the novel systems to resist earthquake forces is StrongBack System (SBS). The SBS comprises two distinct resistance systems that segment the bracing spans into two parts. One component is a vertical truss designed to remain elastic, promoting uniform deformation across the building's height. This configuration facilitates force distribution, thereby delaying the onset of soft-story mechanism. This research focuses on the seismic performance evaluation of exterior StrongBack structural systems in high-rise structures and suggests solutions to improve their seismic performance, by examining two scenarios: (1) a transfer of the exterior elastic truss near the shorter brace, and (2) a transfer near the longer brace. Results indicate that the High-rise SBS structures are vulnerable to collapse and addition of truss elements to the elastic truss near the shorter brace or longer brace significantly enhances the seismic performance of such systems in the severe earthquakes.