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Nominated for Eurosteel 2021 Best Paper Award In recent decades, innovative seismic‐resilient structural systems have been proposed to reduce the direct and indirect losses related to seismic events. Among others, steel moment‐resisting frames (MRFs) equipped with damage‐free self‐centring column bases (SC‐CBs) represent a promising solution. Although several configurations of SC‐CBs have been proposed in literature, only a few research studies investigated how the significant parameters (e. g. number of storeys, frame layout, seismic mass, seismic intensity) affect the seismic performance of MRFs with SC‐CBs. To further investigate this aspect, the present work focuses on the influence of an additional parameter (i. e. the combination of seismic mass and acceleration) on their self‐centring capability. Three 5‐bay steel MRFs with 4, 6 and 8 storeys are considered as case‐study frames and designed based on two different values of the seismic mass (i. e. M1 and M2). Numerical models are developed in OpenSees, incremental dynamic analyses (IDAs) are performed to monitor global engineering demand parameters (EDPs), and fragility curves are derived to evaluate the seismic performance of the structures. It is observed that the inclusion of SC‐CBs produces beneficial effects in terms of increased self‐centring capability on all the investigated case studies. Moreover, the parametric analysis allows some preliminary observations to be drawn regarding the influence of the number of stories and seismic mass.

Low‐damage and self‐centring column base connections have been proposed in the last two decades as innovative solutions able to provide the seismic resilience in Moment Resisting Frames (MRFs). Although many works have demonstrated the benefits deriving from the adoption of these systems, only a few research studies investigated the significant parameters influencing their self‐centring capability. This paper investigates the influence of the frame layout (i.e., storeys and bays number) on the seismic performance of perimeter MRFs equipped with damage‐free self‐centring column bases previously studied by the authors. Nine case‐study perimeter steel MRFs are designed and modelled in OpenSees. Incremental Dynamic Analyses are performed monitoring both global and storey‐level Engineering Demand Parameters, including peak and residual interstorey drifts. Fragility curves are subsequently used to evaluate the self‐centring capability of the structures. The present study provides insights on the use of the adopted connections for the residual drift reduction of MRFs and defines the boundaries of the investigated parameters for their application. Results highlight that the self‐centring behaviour is particularly sensitive to the number of storeys and tends to reduce with the increasing height of MRFs equipped with the proposed connections.