Seismic design and evaluation of controlled rocking outrigger core wall (CROCW) system using equivalent energy design procedure (EEDP)

Abstract

In this paper, a novel earthquake resilient reinforced concrete core wall system named the controlled rocking outrigger core wall (CROCW) system is proposed. The CROCW consists of two high-performance seismic force resisting systems along its two principal axes. Along one principal axis is the controlled outriggered rocking wall (CORW), where an outrigger is situated at the roof and controlled rocking at the base. Dampers are incorporated within the outrigger and the rocking base to allow CORW to provide stable energy dissipation during earthquake excitation. Along the other principal axis is the self-centering coupled wall (SCCW). In the SCCW system, the self-centering friction dampers are incorporated within the coupling beams to dissipate the earthquake energy, while the base is designed to rock. The proposed CROCW system can be designed using the novel equivalent energy design procedure (EEDP). Four prototype buildings (two different building heights and two different building sites) were designed using the EEDP presented in this paper. The detailed nonlinear time history analysis was conducted to assess the performance of CROCW system. The results demonstrate that the CROCW system can be efficiently designed using the EEDP procedure to achieve a superior performance and low damage response at multiple levels of earthquake shaking intensities.