Development of performance prediction method for existing prestressed concrete structures

2024 Fiscal Year Final Research Report

• Project/Area Number: 22K04292
• 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: Chubu University
• Principal Investigator: ITOH Atsushi 中部大学, 工学部, 教授 (00345927)
• Project Period (FY): 2022-04-01 – 2025-03-31
• Keywords: 鋼材破断 / 残存プレストレス分布 / 数値解析 / 性能予測

Outline of Final Research Achievements

This study aimed to develop a numerical analysis method capable of predicting the load-carrying capacity of prestressed concrete members with fractured prestressing tendons, based on experimental and numerical investigations.
Bond tests between tensioned PC tendons and grout, along with numerical analyses, revealed that the bond behavior after tendon fracture varies depending on the magnitude of tendon strain change following fracture or external loading. The improved numerical model enabled accurate prediction of the residual prestress distribution observed in previous fracture experiments. It was also clarified that the bond stress-slip relationship at the fracture location can be represented by a bilinear envelope, whose strength is proportional to the two-thirds power of the grout compressive strength. Furthermore, it was confirmed that the proposed analysis method can reasonably predict the flexural load-carrying capacity of PC members with fractured tendons.

Free Research Field

コンクリート工学

Academic Significance and Societal Importance of the Research Achievements

点検で得られた腐食状況やひび割れ性状を解析モデルに反映させ，解析的にその損傷下の応力状態を評価したのちに構造性能を評価できる解析プラットフォームをI/O部分も含めて開発する。この解析技術の開発により，点検結果をダイレクトに反映させて劣化を深度化させることで，劣化した既設構造物に対して適切な時期に効果的な対策を施す検討などに広く利用されると期待できる。