Introducing a low damage system incorporating rocking braced frame and resilient slip friction joint as a shear key

Abstract

In this paper, to achieve a self-centring damage avoidance rocking framed system, RSFJ has been employed as a shear link between braced frame and its boundary columns. Such a system could be used for a single or coupled braced frame. This system could be adopted as an alternative to conventional rocking systems to reduce their design’s complexity and implementation challenges. Covering taller rocking systems is another advantage of such a configuration. In this study, the performance of this configuration has been studied and assessed, then to evaluate the seismic performance of the introduced system the results have been compared with an isolated braced frame ( LRB isolation at the ground level). The case study, include a seven-story prototype building equipped with a conventional special braced frame. As the results demonstrate, the proposed rocking system could provide structures with a fully self-centring low damage lateral system which is a crucial factor to evaluate the required time and cost for building rehabilitation. The self-centring capability of a system also minimises the vulnerability of structures against severe aftershocks on consecutive seismic events. Furthermore, like the base-isolating concept, the rocking systems rely on shifting the fundamental mode to decline the transmitted forces, so compare to the ordinary braced frame, the absorbed energy would be at a lower rate. However, as the rocking systems are under the influence of higher mode effect to improve its efficiency, the influence of having multiple rocking levels also have been studied.