High-precision simple analysis method and seismic verification that can consider the post-peak behavior of the concrete filled structure

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K04337
• 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: National Institute of Technology, Toyota College
• Principal Investigator: Naoki Kawanishi 豊田工業高等専門学校, 環境都市工学科, 教授 (60300589)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: コンクリート充填構造 / CFT / 簡易解析 / 耐震設計 / 連続高架橋 / ポストピーク

Outline of Final Research Achievements

Until now, for structures in which concrete is filled in steel cross-section columns (CFT structure), a method for easily estimating the mechanical behavior after the peak load has not been established. In this study, we proposed a new unique method for tracking the behavior of the CFT structure after the peak load easily and accurately, and compared it with the experimental results and FEM analysis results of the existing CFT structure to improve its accuracy. From these results, it was clarified that the proposed model can accurately trace the macrodynamic behavior of CFT even in the region after the peak load. We also proposed a new seismic design method with high rationality for continuous viaducts with CFT piers using the proposed model.

Free Research Field

構造工学

Academic Significance and Societal Importance of the Research Achievements

エネルギー吸収能に優れたCFT構造は鋼材の非線形性に加えてコンクリートと鋼の接触挙動など複雑な非線形挙動が表れるため，最大荷重以降の力学挙動を簡便に推定する手法が確立されていなかった．本研究では，簡易かつ精度よくCFT構造のポストピーク域の力学挙動を追跡可能なモデルを独自開発し，世界ではじめてその精度検証に成功した．さらに，この簡易モデルを利用することでCFT構造を含んだより複雑な構造物の応答計算も可能になるため，残存耐力に基づいた直接的で精度の高い耐震設計法についても提案できたため，より自由度の高い経済的なCFT構造の構築に寄与できたものと考えられる．