Fatigue Durability of Steel-Concrete Composite Girder Bridges due to Fire

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K04673
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 22020:Structure engineering and earthquake engineering-related
• Research Institution: Osaka Institute of Technology
• Principal Investigator: Ohyama Osamu 大阪工業大学, 工学部, 教授 (70411410)
• Co-Investigator(Kenkyū-buntansha): 今川 雄亮 大阪工業大学, 工学部, 准教授 (00804121)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 橋梁火災 / 熱履歴 / 合成桁 / 疲労耐久性

Outline of Final Research Achievements

Recently, the fire attack for bridges due to a tank lorry vehicle turning over accident, incendiary fire and so on trends to increase in Japan and in foreign countries. At present, the diagnosis and repair method of the existing bridge infrastructure damaged by fire have not been standardized yet in Japan. Therefore, to determine the passing propriety of the composite girder bridges after fire, we carried out the fire test by using the External fire curve ruled in Eurocode to clarify the distribution of the temperature and condition of lower concrete slab. Next, we try to determination of passing propriety in the composite girder bridges based on the results of fatigue test.
From fatigue test, the composite girder subjected to thermal history failed after 780,000 cycles. On the other hand, there was no slip between steel girder and composite slab that had not been subjected to thermal history after 1 million cycles.

Free Research Field

複合構造学

Academic Significance and Societal Importance of the Research Achievements

本研究成果の学術的意義や社会的意義は，既往の結果も含めて，建設頻度の高い鋼・コンクリート合成桁橋が熱影響を受けた後の通行可否を瞬時にかつ正確に判断するための評価手法を示すことが可能となる．
また，得られた結果より，鋼桁やコンクリート床版の補修工法の提案にも繋がり，社会に貢献できると考えられる．