Establishment of a Continuously Usable Damping Element Joining Method for Unbonded PC Structural Beam

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K14876
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 23010:Building structures and materials-related
• Research Institution: Kanagawa University
• Principal Investigator: shirai yuki 神奈川大学, 建築学部, 助教 (00779720)
• Project Period (FY): 2020-04-01 – 2022-03-31
• Keywords: コンクリート系 / アンボンドプレストレスト / 梁 / エネルギ吸収能力

Outline of Final Research Achievements

First, a buckling restrained brace, a compact damping element that can be attached to the end of a member of an unbonded prestressed concrete beam, has been developed. The brace utilizes the difference between the cross-sectional area of a deformed steel bar at a sectional section and the cross-sectional area of a sectional cross section, and has a prescribed load carrying capacity and damping performance with a mass of about 10 kg. Experiments on beam members showed that the thin resilience characteristic of unbonded prestressed concrete and the resulting low energy absorption capacity were improved, and that the bearing capacity increased by a factor of 1.25 and the energy absorption capacity by a factor of 2 at 1/100 member angle. Furthermore, a repair and reinforcement method for the continuous use of damaged beams was proposed and its effectiveness was also confirmed.

Free Research Field

構造力学

Academic Significance and Societal Importance of the Research Achievements

プレストレストコンクリート構造は部材を工場で製造し，現地で組み立てる構法である。そのため，人員を削減できたり，環境負荷を低減できる。一方で，地震時に揺れが大きくなる可能性があるため，地震のエネルギを吸収するダンパーを設置する方法を検討した。本研究の成果として，開口を大きくとれる小型のダンパーを開発し，部材の耐震性能が向上することを確認した。また，地震などにより損傷を受けた部材を継続して使用するための。補修・補強方法も提案した。