Design concepts and seismic behavior of ductile linked rocking steel frames.

This paper proposes a novel ductile linked rocking steel frame (DLRF) that relying on gravity load and rocking column base components rather than post-tensioning elements to provide the self-centering capacity. In the DLRF, rocking steel braced frames remain elastic by being permitted to uplift and rock at the rocking column bases, coupled with ductile links that act as structural fuses to dissipate energy through accommodating vertical movement between the two-rocking steel braced frames. Rocking column bases can dissipate energy through fuses that can be repaired easily by being bolted to the column. The design equations to govern the corresponding resistance mechanism of the DLRF for each limit state are presented and applied to a four-story prototype structure. Nonlinear dynamic analyses were performed to examine the behavior of the DLRF. The seismic performance of the DLRF is contrasted with a corresponding fixed-base structure, in which the column base is designed as a rigid connection. The comparison indicated that the DLRF exhibited uniformed interstory drift distribution as well as negligible residual drift subjected to DBE and MCE intensities, and thus the soft-story failure can be effectively avoided. Dynamic analyses also confirmed that the proposed design equations can predict the mechanical behavior of the DLRF with expected drift capacity and flag-shaped hysteretic response. Therefore, the proposed DLRF is a viable alternative to a seismic load-resisting system which could avoid severe and expensive damage to the structure, enhancing resilience capacity. • The ductile linked rocking steel frames (DLRF) showing flag-shaped response was introduced. • The rocking column bases can recenter the frame and ductile links can enhance energy dissipation. • The design equations based on specified performance objectives were proposed and validated. • The DLRF exhibits uniformed interstory drift distribution and reduced residual drifts. • The DLRF can perform as predicted with rocking and self-centering behavior. [ABSTRACT FROM AUTHOR]