氏家 大介*1・安田 聡*1・田中 昂平*1・成原 弘之*2・松本 修一*3



*1 技術センター 都市基盤技術研究部 構造研究室
*2 技術センター 都市基盤技術研究部
*3 設計本部 設計企画部

Development of Buckling-restrained Brace with H-shaped Cross-section

Daisuke UJIIE*1, Satoshi YASUDA*1, Kohei TANAKA*1, Hiroyuki NARIHARA*2 and Shuichi MATSUMOTO*3

A buckling-restrained brace is a steel brace with equal strength and deformation performance in tension and compression, consisting of a core member that bears the axial force and a buckling stiffener that prevents buckling when the core member is compressed. More than 20 years have passed since the development of our buckling-restrained brace "Shape-Up-Brace," and it has been widely used as a seismic-resistant member for medium- and low-rise buildings and as a vibration-control member for high-rise buildings. However due to the rise in steel prices in recent years, its price advantage over competing products has been undermined. In response, a new buckling-restrained brace was developed using rolled H-shaped steel as the core member and mortar-filled square steel tubes as buckling stiffeners to reduce fabrication costs without sacrificing structural performance. In the development of the brace, structural tests were conducted using 15 full-size specimens to confirm the equivalent plastic deformation performance in tension and compression, and to verify the stiffening effect of the buckling stiffener and the applicability of existing design methods for the out-of-plane buckling behavior of the joints. Also, low-cycle fatigue tests using low-yield-strength steel were also conducted to understand the performance as seismic-damping members.

Keywords: Buckling-restrained brace, H-shaped steel, mortar-filled square steel tube, structural test

*1 Structure Research Section, Urban Engineering Research Department, Taisei Advanced Center of Technology
*2 Urban Engineering Research Department, Taisei Advanced Center of Technology
*3 Operations Planning Department, Design Division