Verification of wind-induced instabilities of structures against future super typhoons

2023 Fiscal Year Final Research Report

• Project/Area Number: 20H02232
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 22020:Structure engineering and earthquake engineering-related
• Research Institution: Kyoto University
• Principal Investigator: Yagi Tomomi 京都大学, 工学研究科, 教授 (30293905)
• Co-Investigator(Kenkyū-buntansha): 野口 恭平 京都大学, 工学研究科, 助教 (70802685) ; 松宮 央登 京都大学, 工学研究科, 准教授 (70516640)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 耐風安定性 / 空力振動 / 風洞実験 / 数値風洞実験 / 渦励振 / フラッター / 橋梁 / 高欄

Outline of Final Research Achievements

Considering the possibility of unexpected strong winds acting on structures due to climate change in the future, we have studied the practical application of numerical wind tunnel experiments as an alternative to conventional wind tunnel experiments as a method of verifying safety, as well as the clarification of phenomena and verification methods for the response behavior of structures under unknown high wind velocity conditions. In the former case, modeling the small details of structures such as railings is the most important issue, and we proposed a realistic method to replace them with simple porous medias. New knowledge was also obtained on the effects of small details on various aerodynamic vibration phenomena. In the latter case, we measured the aerodynamic forces of structures rotating in a wind tunnel, formulated new aerodynamic forces that takes into account the effect of relative angular velocity of attack, and established a method for evaluating the response amplitude.

Free Research Field

耐風工学

Academic Significance and Societal Importance of the Research Achievements

長大構造物の耐風安定性を数値流体解析によって照査することは、既に技術的には可能であるが、構造物の微細部を再現すると計算コストがまだ高いのが現状である。本研究では、気流の剥離点付近の微細部を簡易なモデルで置き換えることで、数値風洞を耐風設計に利用する可能性を提案した。また、構造微細部の空気力学的影響を調査し、種々の空力振動現象に関する新しい知見を得ることができた。さらに、従来の耐風安定性の照査においては、照査風速において構造物に不適切な振動現象が発生するかしないかの判断のみであったが、照査風速を超える想定外の風速において、大振幅の応答評価ならびに現象解明が可能な方法を提案することに成功した。