Search for: All records

Structural engineering is moving towards the design of enhanced performing buildings under earthquake events to improve the resiliency of urban communities. Buckling Restrained Braced Frames (BRBF) have been widely adopted to resist lateral loads. However, typical configurations could be subjected to drift concentration, leading to large story drifts and uneven utilization of the BRBs with building height. Studies have suggested that innovative configurations, such as pivoting or rocking frames, can provide a better distribution of the story drift by delaying or preventing story mechanisms and spreading the energy dissipation to adjacent stories across the building height. These types of bracing configurations utilize as essentially elastic spine, or strongback, to induce a global tilting mode. However, since the spine is designed to remain elastic, additional design considerations are needed to size the elements in strongbacks. This study presents a comparative study between traditional chevron BRBF and strongback BRBF systems for a set of buildings with different heights and tributary areas. Results show that the pivoting and rocking strongback result in reduced the peak story drift with more uniform distribution of drift demands. The cost of these alternatives, per frame, was similar to the chevron BRBF.