The method to restrict the increase of strength of hollow steel bridge pier by in-filled concrete for seismic retrofitting

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K04322
• 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: Nagoya Institute of Technology
• Principal Investigator: Ebisawa Takemasa 名古屋工業大学, 工学(系)研究科(研究院), 助教 (90332709)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 耐震設計 / 鋼製橋脚 / 補強 / CFT / 変形能 / 耐力

Outline of Final Research Achievements

For seismic retrofitting of the hollow steel pier, the method that concrete is filled in the pier is often used. In this study, to restrict increasing of the strength of the pier by in-filled concrete, the middle weak layer is introduced in the in-filled concrete. The increasing of the strength of the pier is controlled by appropriate strength, stiffness, thickness and position of the weak layer. The effect of the weak layer was examined by the static tests of the steel piers and the behavior of static tests was predicted by the numerical analysis.

Free Research Field

耐震工学，構造工学，計算力学

Academic Significance and Societal Importance of the Research Achievements

中空鋼製柱のCFT化は必ずしも望ましくない耐力上昇をもたらす．既設構造では基礎の補強が困難であるので，基礎の耐力がCFT化で上昇した柱の耐力を下回ることも稀ではなく，地震時に基礎の損傷が先行すると柱が十分な耐震性能を発揮できないという問題が生じる．充填コンクリートに中間弱層を設けた2相構造を導入することで，CFT柱の変形性能を保持しつつ耐力上昇を抑制するという従来のCFT化では不可能であった2つの要素を独立に制御ができるようになる．したがって，従来CFT化による鋼製柱の耐震補強法でのネックであった上記問題は，本試みにより解消され，CFT化による耐震補強が容易になる．