ABSTRACT In February 2023, a comprehensive series of shaking table tests were conducted at the E‐Defense facility, the world's largest three‐dimensional earthquake simulator, on a full‐scale 10‐story steel moment‐resisting frame supplemented with BRBs. The primary goals are to collect valuable data for advancing state‐of‐the‐art seismic structural techniques and evaluating numerical analysis models. The main objectives of this paper are: (1) to validate the seismic capacity of a mid‐rise building designed according to current Japanese building standards and guidelines, and (2) to examine the contribution of BRBs to seismic performance. The specimen building system consists of a moment‐resisting frame system in the transverse direction and a frame system with multi‐story buckling‐restrained braces in the longitudinal direction. The specimen realistically incorporated reinforced concrete floor slabs, exterior materials, and interior equipment. This paper mainly reports the test results for the global and local seismic responses of the conventional steel seismic resisting system. Subjected to JMA Kobe earthquake motions at amplitudes of 25%, 50%, 75%, and 100%, the specimen exhibited stability despite the story drift ratio exceeding 2% during extreme motion beyond the design earthquake. Removal of four BRBs at the third story, simulating BRB fracture, resulted in a significant increase in the maximum story drift ratio in the longitudinal direction (73.5% and 53.5% for JMA Kobe 25% and 75% excitations, respectively). Under 100% excitation, BRBs contributed 21% to story shear and 38% to energy dissipation for the third story. These findings highlight the effectiveness of BRBs in enhancing the seismic performance of MRFs and provide critical insights for advancing earthquake‐resistant design practices.
Fujiwara et al. (Fri,) studied this question.