Improvement of Bearing Failure Behavior on T-shaped S Beam-RC Column Joints with Small Column

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K04448
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 23010:Building structures and materials-related
• Research Institution: Osaka Institute of Technology
• Principal Investigator: NISHIMURA Yasushi 大阪工業大学, 工学部, 教授 (10102998)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 鋼コンクリートハイブリッド構造 / 柱RC・梁S / 小鉄骨 / 支圧性能の改善 / 埋込み長さ / 補強法 / 支圧抵抗機構 / 支圧耐力評価法

Outline of Final Research Achievements

To improve the bearing failure behavior of T-shaped S beam - RC column joints, joint detail using small column was proposed. Small column was attached on the bottom flange of the embedded steel beam at right angles to the steel flange. The objective of this study was to clarify the effectiveness of proposed joint detail experimentally and theoretically.
From the test results, it was clarified that flexural strength of the small column can be developed if the embedded length of the small column is 3 times longer than the depth of small column. The reinforcing bars that were placed around the small column and the depth of the small column were very important factors to improve the bearing failure performance. Furthermore, based on the stress transferring mechanism and resistance mechanism of the joints proposed by previous studies of author, the design formulae of joints with small column were proposed. The predictions were shown to be in good agreement with the test results.

Free Research Field

建築構造学

Academic Significance and Societal Importance of the Research Achievements

鋼コンクリートハイブリッド構造柱梁接合部特有のS部材に接するコンクリートの支圧破壊は構造性能上避けるべき破壊形式である。
本研究は、この支圧破壊を抑制する目的から、小鉄骨を用いた柱梁接合部ディテールの実用化に向けた検討を実施し、その可能性を示した。このディテールは非常に簡便で、施工の大幅な改善を図ることができる点において社会的意義がある。また、小鉄骨を有する接合部の支圧終局耐力について、力学モデルに基づく耐力評価法を示した。この力学モデルは他のハイブリッド構造接合部に直接応用できるものであり、この点において大きな学術的意義がある。