Construction of evaluating equations for shear capacity of existing RC structural members based on the shear resistance mechanisms

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K14813
• 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: Nihon University
• Principal Investigator: YAMADA Yuta 日本大学, 理工学部, 助教 (90801035)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: せん断 / RCはり / アーチ機構 / ビーム機構 / 補修 / 補強 / 鉄筋腐食ひび割れ / FRPシート

Outline of Final Research Achievements

The shear resistance mechanisms of deteriorated reinforced concrete (RC) members with strengthening and / or repairing materials were made clear. Simultaneously, the evaluation models to predict shear strengths of those members were constructed based on the definition of the shear resistance mechanisms. The contribution forces of materials to the shear resistance were classified based on the constructed models. Eventually, the theoretical evaluation equation of shear strengths was constructed by the knowledge obtained above. The accuracy of the constructed evaluation equation was compared with that of the ones adopted to major specifications and design codes. As a result, the constructed equation indicated higher accuracy in case of the members without deteriorations, and that the accuracy was maintained even in case of the deteriorated members with strengthening and / or repairing materials.

Free Research Field

コンクリート構造

Academic Significance and Societal Importance of the Research Achievements

RC構造部材のせん断破壊は避けるべき破壊形態の1つであるものの，その現象の複雑さゆえに合理的な耐力予測式の構築には至っておらず，主要な設計指針類の多くには統計的な評価手法が採用されている．劣化した部材や補修および補強された部材に対しては，統計的な評価手法の適用は困難である．本研究では，このような部材に対しても一貫して耐荷性能を評価可能な理論的な評価式を構築しており，既設構造部材における維持管理手法の高度化に資する成果が得られた点に社会的意義がある．構築した評価式はせん断耐荷機構の定義に立脚した理論式であることから，せん断耐力評価手法の理論化に資する成果が得られた点に学術的意義がある．