可變勁度之雙核心自復位斜撐與夾型挫屈束制斜撐於一層樓子構架耐震試驗

Abstract

根據以往的研究顯示自復位斜撐構架擁有較低的殘餘變形，遠小於挫屈束制斜撐構架，然而自復位斜撐構架具有較高的初始彈性勁度，導致輸入的地震力增加。為了解決此問題，本研究的重點之一是設計可變初始彈性勁度並增加軸向變形能力的自復位斜撐，其中使用碟型彈簧以降低自復位斜撐的初始彈性勁度。第二個研究重點是基於林皇佐（2023）的三層樓鋼造結構振動台實驗的子構架試驗，該試驗中使用了滑動樓板系統，其中使用水平夾型挫屈束制支撐將樓板與構架連接，以減低結構物受地震力之下的樓板慣性力。本研究將探討此滑動樓板系統於子構架中的行為，並運用試驗結果於三層樓振動台試驗中。 本研究有兩個試驗項目，第一個項目是含碟型彈簧與消能鋼筋的自復位斜撐一層樓構架試驗，該試驗探討了可變勁度之自復位斜撐構架的耐震行為，並比較自復位斜撐構架和夾型挫屈束制斜撐構架的反應。第二個項目是三層樓振動台中的一層樓滑動樓板子構架試驗，用於驗證新型結構系統的可行性，測試新的消能機制於鋼構架系統中的性能，並優化消能裝置及其接合方式之設計。 實驗結果顯示可變勁度之自復位斜撐構架在標準載重試驗下具有良好的自復位能力和對稱的遲滯消能行為，並且斜撐行為與預測模型相符，顯示使用碟型彈簧可以有效降低其初始彈性勁度。而於滑動樓板試驗結果顯示，水平夾型挫屈束制支撐顯示良好的消能能力，並且於試驗後水平消能構件接頭及構架皆維持彈性，並運用此設計於三層樓振動台試驗中。

Based on previous research, self-centering braces (SCB) have shown lower residual deformation compared to buckling-restrained braces (BRB). However, SCB has higher initial elastic stiffness, leading to increased seismic forces. To address this, the study aims to design a SCB with adjustable initial elastic stiffness and increased axial deformation capacity using disc springs. The second research focus is the substructure testing based on the three-story steel frame shaking table experiment conducted by Chou and Lin (2023). This experiment utilizes a sliding slab system, connecting the slab and the frame using a horizontal BRB to reduce the inertia force of the slab under seismic forces. The study aims to investigate the behavior of this sliding slab system in the substructure and apply the test results to the three-story shaking table experiment. There are two test projects in this study. The first project is a one-story frame test with SCB incorporating disc springs and energy dissipating rebars, comparing the seismic response of SCB with disc springs to BRB. The second project is a one-story sliding slab substructure in a three-story frame, aiming to verify the feasibility of the new structural system, test the performance of the new energy dissipation mechanism, and optimize the design of the energy dissipation devices and their connections. The experimental results show that the one-story SCB frame exhibits good self-centering ability and symmetric hysteretic energy dissipation behavior under standard loading tests, aligning with predicted models and confirming the effective reduction of initial elastic stiffness using disc springs. The sliding slab test demonstrates the good energy dissipation capacity of horizontal BRBs, with elastic connections between the horizontal energy dissipation device and the frame. This design concept has been applied to the three-story shaking table test.