Simple method for estimating seismic performance of a frame with displacement-dependent dampers using Multi-spring model

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K04333
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 23010:Building structures and materials-related
• Research Institution: Nagoya University
• Principal Investigator: Mori Yasuhiro 名古屋大学, 環境学研究科, 教授 (30262877)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 履歴ダンパー / 制振構造物 / 性能設計 / 累積塑性変形倍率 / マルチスプリングモデル

Outline of Final Research Achievements

It is found that there exists approximate linear relationship between the logarithms of the ratio of the cumulative plastic deformation of each elasto-plastic spring in a Multi-spring (MS) model, which is equivalent to each modal response of a frame with displacement-dependent passive dampers and each spring represents the dampers installed to the each story of the frame, to the ratio of yield displacement of each spring to the minimum yield displacement among the springs. Then the slope of the relationship can be modeled as a simple function of the maximum ductility of the MS model regardless of the number of the stories in the frame, amount of the dampers installed, and the arrangement of the dampers. Using the relationship and the total hysteresis energy of the MS model, a simple method for estimating the hysteresis energy of each spring in the MS model is proposed. By summing up the energy mode-wise, the cumulative plastic deformation of the dampers in each story can be estimated.

Free Research Field

建築構造学

Academic Significance and Societal Importance of the Research Achievements

履歴ダンパーは，極めて稀に発生する大地震に対して建物の機能性保持能力を向上する手段の一つである。その要求性能の一つである累積塑性変形倍率を，地震動特性の不確定性や建物の構造特性考慮しながら各次MSモデルの総累積塑性ひずみエネルギーから簡易にかつ精度良く評価できる方法を提案する本研究成果の学術的意義は大きい。この手法を地震のエネルギーを指標とした確率論的地震ハザード情報と組み合わせることで，実用的な耐震性能評価法へ展開することで，耐震性能水準の定量的表現によって制振構造の費用対効果が明確となり，その採用の動機付けとなるだけでなく，長寿命化を見据えた良質な社会ストックの形成にも貢献できる。