民國88 年發生的912 地震反應出國中小校舍耐震能力普遍不足之問題,各方學者對此亦提出對應之補強工法,其中,剪力牆補強為一常見的補強方法。惟有鑒於剪力牆補強之後,雖可大幅提升結構耐震性質,但難以滿足既有校舍對於通風及採光之需求,有鑑於此,本研究參考台南市後甲國中德育樓之結構配置,規劃一系列開口剪力牆補強試體進行試驗研究,以探討開門或開窗的剪力牆補強試體之耐震行。 為了能符合目前現有的校舍型式,本次試驗分別以柱間淨跨度300 公分及420公分兩種校舍常見的構架尺度,共規劃了八組試體進行試驗,其中包含兩組空構架試體以及六組開口剪力牆補強試體,於國家地震工程研究中心實驗室進行反覆側推試驗。本試驗所規劃的開口剪力牆補強試體,為考量校舍建築的實際使用情形,以採光通風佳的大面積開口為原則,此外試體開口位置皆為對稱配置,以利未來能建立一套有效且可靠的開口RC 牆補強耐震評估方式及補強施工準則給工程師參考使用。 實驗結果顯示,大開口RC 牆補強試體,可提昇約3.8 倍的側向強度、提昇至少13 倍的勁度;小開口RC 牆補強試體,可提昇約6.8 倍的側向強度、提昇至少34 倍的勁度。且於試體喪失垂直乘載能力之前測試層間變位角均可達2 %,表示開口鋼筋混凝土牆補強可直接應用在校舍等低矮型建築物上。而以校舍手冊三版所建議的評估方法為主軸,再加以修改過後的評估曲線均能保守的評估試驗結果。
Lots of elementary and secondary school buildings were damaged by the devastating 921 Chi-Chi earthquake, so scholars proposed methods for increasing the seismic performance of school buildings. Adding shear wall method is a common method to be used in school buildings retrofit. However, by the use of retrofit of adding shear wall, it is difficult to satisfy the lighting and ventilation requirements for school building. Consequently, National Center for Research on Earthquake Engineering (NCREE) planned a series of specimens retrofitted by RC walls with window and door opening to study the feasibility of the proposed method. The specimens were designed according to existing school buildings. In order to comply with existing schools buildings, two common spans, 300 cm and 420 cm, were considered in the experimental plan. This experiment includes eight specimens, which are two bare-frame specimens and six retrofitted specimens. Considering the lighting and ventilation of school buildings, large opening is main principle. Also, the specimen was designed in symmetric configuration, in order to facilitate and establish an effective and reliable seismic evaluation method of RC walls with openings for engineers in the future. Experimental results show that the large-opening specimens can enhance about 3.8 times of lateral strength, at least 13 times of stiffness; the small-opening specimens can enhance about 6.8 times of lateral strength, at least 34 times of stiffness. Drift ratio of all specimens can be up to 2%, it means that the retrofit by RC wall with opening can be applied directly to the low-rise school buildings. The force-displacement curves of all specimens are predicted base on the third-edition Evaluation and Retrofit Handbook for School Buildings. All prediction results are conservative after modification.