Incorporation of hysteretic devices on bracing systems of low invasivity. A new approach for the seismic redesign of framed structures

As an alternative solution to the severe structural invasion of bracing systems for seismic redesign, this paper presents new configurations of dissipative bracing systems with characteristics of low invasivity. The geometry of the proposed systems is either a smooth arch or a polygonal arch of 4 members. Each bracing arch contains six hysteretic devices and the geometry of the arch is such that favours device activation.The proposed bracing system combines the benefits of the passive control of the initial period of the structure (before devices are activated) with that of a bracing system with stable inelastic response and high energy dissipation capacity. A series of inelastic nonlinear time-history analyses of original and redesigned models under the action of damaging earthquake records confirm the effectiveness of the proposed dissipative bracing system.