Force-Based Design Method for Force-Limiting Deformable Connections in Earthquake-Resistant Buildings

Abstract

This paper proposes a force-based design method for force-limiting deformable connections that are used to transfer seismic-induced horizontal forces from the floor diaphragms in buildings to the vertical elements of lateral seismic force–resisting systems with base flexural mechanisms (e.g., reinforced concrete shear walls). The design method determines the limiting forces for the connections at each floor of the building. The limiting forces for the connections are the forces at which the force-limiting deformable connections transition from linear-elastic to post-elastic response. Design examples are presented. Seismic responses from numerical simulations of 12-, 8-, and 4-story reinforced concrete shear wall example buildings show that the proposed method enables effective preliminary design of the force-limiting deformable connections. It is shown that the buildings with connections designed with the proposed method have relatively uniform distribution of connection deformation demands over the building height. It is also shown that their seismic force and acceleration responses have reduced magnitude and reduced variability compared to conventional buildings that exhibit large variability in their acceleration responses.