Rationalization of Joint Structure in FRP Bridge Barriers Considering Structural System Behavior

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K14234
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 22020:Structure engineering and earthquake engineering-related
• Research Institution: Osaka Metropolitan University (2022-2023); Osaka City University (2021)
• Principal Investigator: HAYASHI Gen 大阪公立大学, 大学院工学研究科, 助教 (10869530)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 複合材料 / 高力ボルト摩擦接合 / 引張接合 / 長期リラクセーション特性

Outline of Final Research Achievements

In this study, research on high-strength bolted frictional GFRP joints was conducted with the goal of rationalizing the joint structure of GFRP bridge barriers. The results showed that joint surface treatments, such as galvanizing the connecting plate and fluororesin coating the base metal, significantly affected the slipping capacity in the slip joint experiments. Reproduction analysis indicated that the variation of the shear modulus had a significant effect on the slipping behavior. Bending experiments at the base of full-scale GFRP bridge barriers confirmed the frictional behavior and failure modes, quantitatively evaluating the initial stiffness and stress distribution. Furthermore, the effects of galvanized steel and fiber volume content on bolt axial force were evaluated in long-term relaxation tests, leading to the proposal of a prediction equation for the reduction of bolt axial force.

Free Research Field

複合材料，接合構造，橋梁工学

Academic Significance and Societal Importance of the Research Achievements

本研究は施工性や維持管理性の優れた実務上の要請に応え得る橋梁付属物の設計の一助となる検討である．構造材料としてFRPを用いることで重機を使用せずとも施工可能となることで施工性を良くし，従来の構造材料では実現できない高耐久性の橋梁付属物であるからである．また，本研究の試みたFRP部材の接合部における高力ボルト摩擦接合は，有効性が高く，今後，大型土木構造物への波及効果も期待される．