Practical application and construction process optimization of technology for improving fatigue resistance of narrow welds in steel plate decks of highway bridges

2023 Fiscal Year Final Research Report

• Project/Area Number: 19KK0366
• Research Category: Fund for the Promotion of Joint International Research (Fostering Joint International Research (A))
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 22020:Structure engineering and earthquake engineering-related
• Research Institution: Osaka University
• Principal Investigator: Hirohata Mikihito 大阪大学, 大学院工学研究科, 准教授 (50565140)
• Project Period (FY): 2020 – 2023
• Keywords: 鋼床版 / 道路橋 / 溶接 / 疲労

Outline of Final Research Achievements

In this study, research on the application of fatigue resistance improvement using residual stress reduction by local heating, which was developed by the applicant, to welds of narrow structures in steel decks of highway bridges, was conducted in an international joint organization. The research was conducted in cooperation with Prof. Jarmai of the University of Miskolc, Hungary, on the optimization of the construction process and the approach from an economic viewpoint, which are useful for the practical application of this technology. The method to rationally evaluate fatigue durability was also studied in cooperation with Prof. Chang of Chung-Ang University, Seoul, Korea. The obtained results were submitted as international co-authored papers. In addition, we established a continuous cooperative system with the possibility of future development, such as the possibility of applying the method to different structures.

Free Research Field

構造工学

Academic Significance and Societal Importance of the Research Achievements

本研究では，道路橋鋼床版の実寸法を想定した溶接部に対し，局所加熱による残留応力低減を効果的に適用するための条件探索を実施した。また，残留応力低減による耐疲労性向上効果を合理的に評価する手法を提示した。これらの点は，本技術の実用展開に向け，学術的に大きな意義を有する。さらに，橋梁に代表されるインフラ構造物の耐久性向上に資する成果を提示したことは社会的に大きな意義を有する。また，国際共同研究，共著論文の公表を通じて本技術の有用性を国際的にアピールする機会を得たことの意義も大きいと考えられる。