鋼筋混凝土開孔牆之側力位移曲線預測

Prediction of Lateral Load Deflection Curve of Reinforced Concrete Wall with Openings

蔡仁傑(Ren-Jie Tsai)

指導教授 ： 黃世建

國立臺灣大學/工學院/土木工程學研究所/碩士(2015年)

https://doi.org/10.6342/NTU.2015.02809

摘要

現今建築結構中常配置許多外牆與隔間牆。但是因為使用性的需求，這些牆具有大量的門或窗開口。由於當今工程界對於開口牆之耐震能力不甚了解，故於耐震分析與設計上常將開口牆之貢獻予以忽略或是過度折減使用，造成住宅建築之耐震能力被嚴重低估，這對建築結構之耐震設計、評估與補強工作非常不利。所以本研究建議一套評估開口牆側力位移曲線的方法，模擬開口牆於剪力破壞下之耐震行為。
本研究建議之開口牆側力位移曲線分析模型，係利用開口造成幾何不連續斷面切割出的區塊，從中決定關鍵桿件與傳力路徑。所謂關鍵桿件係指垂直牆段、牆墩與柱，本研究對建立傳力路徑之規則提出建議，更對牆段側力位移曲線之預測提出有效簡化的方法。傳力路徑之勁度係對路徑內各桿件之勁度作串聯而得，開口牆之勁度則對所有路徑之勁度作並聯而得。透過勁度之比例關係，可將關鍵桿件之側力位移曲線轉換為路徑之側力位移曲線，再將各路徑之側力位移曲線作疊加，則得開口牆之側力位移曲線。
為了驗證建議之開口牆分析模型的準確性，本研究蒐集了國內外開口牆之實驗數據共兩篇，並分析其開口牆試體。整體分析結果與實驗數據比較，可看到有合理之預測值。本研究建議剪力牆開口之分析模型，其計算程序簡易且能合理預測開口牆之側力位移曲線，其有助於工程結構設計以及評估。

關鍵字

鋼筋混凝土 ； 開口牆 ； 側力位移曲線 ； 軟化壓拉桿模型 ； 傳力路徑

並列摘要

Reinforced concrete walls are commonly used in modern residential buildings. Due to functional requirement, openings of doors and windows are often required for these walls. Since the seismic behavior of walls with openings is still unclean to engineers, the walls with openings are often neglected during seismic assessment. Ignoring the seismic resistance of walls with openings will highly underestimate the seismic capacity of residential buildings. It is detrimental for seismic design and retrofitting of building structures. This study proposed a simple analytical model for lateral load-deflection curve of walls with openings subjected to shear failures.
Openings usually create weak zones within wall panels. The proposed model is applicable only to the walls with a single weak zone consisting of vertical wall segments, wall piers and columns. The lateral load-deflection curves of these key elements are first estimated individually and then combined based on the shear stiffness of elements. The rules to select load paths and formation of stiffness relationship and suggested in this study.
In order to verify the propose model, two series of tests of RC walls with openings are compared with analytic results. It can be shown that the propose model can yield reasonable prediction of lateral load-deflection curves. The proposed model is simple and useful for seismic design and retrofitting of RC residual buildings.

並列關鍵字

reinforced concrete ； wall with opening ； lateral load deflection curve ； soften strut and tie model ； transfer mechanism

參考文獻

[16] 李翼安、邱聰智、蕭輔沛、黃世建，「鋼筋混凝土短柱受剪破壞之耐震評估研究」，結構工程，第29卷，第1期，2014，第45-62頁。

[8] 蕭輔沛，鍾立來，葉勇凱，簡文郁，沈文成，邱聰智，周德光，趙宜峰，翁樸文，楊耀昇，褚有倫，凃耀賢，柴駿甫，黃世建，「校舍結構耐震評估與補強技術手冊（第三版）」，國家地震工程研究中心研究報告，NCREE 13-023，台北，2013。

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