為滿足使用性,住宅建築之鋼筋混凝土牆常具有門型或窗型開孔。為經濟有效地對街屋作設計、耐震評估與補強,應不可忽略開孔RC牆之耐震能力貢獻。一般開孔將RC牆分割出不同的牆段,在台灣一般震損調查中,可發現破壞經常集中在開孔左右兩側之垂直牆段上,故本研究主要在探討垂直牆段剪力元素之選取與剪力強度之計算。 美國ACI 318-14規範,規定在開孔附近之牆墩須額外配置水平鋼筋,同樣的道理,在開孔附近之垂直牆段上應也需要此鋼筋之配置。故本研究旨在探討開孔上下方鋼筋配置數量對垂直牆段剪力強度之影響。本文執行4片RC牆實驗以作探討,透過試體裂縫發展之觀察,說明水平鋼筋對垂直牆段剪力強度之影響。除了報告實驗觀察外,本文將實驗量測之剪力強度與ACI 318-14規範之預測值作比較,並建議適用之壓拉桿模型預測方法。
In order to fulfill the serviceability, there are many door or window openings in the reinforced concrete walls of residential buildings. For the building design and retrofitting with economy and efficiency, we have to consider the contribution of wall with opening in the seismic evaluation. The seismic capacity of the RC walls with openings should not be ignored. Opening in the RC wall creates different kinds of wall segments. The earthquake reconnaissance in Taiwan found that the damage of RC walls is mainly concentrated on the vertical wall segments next to openings. Therefore, this research is mainly on how to select the shear elements and how to calculate the shear strength of the vertical wall segments. The ACI 318-14 code required that additional horizontal reinforcement should be provided for the wall piers. Similarly, this horizontal reinforcement should also be provided for the vertical wall segments. Therefore, the objective of this research is to study the effects of different reinforcement configuration around opening on the shear strength of RC walls. In this study, four RC wall experiments were carried out to investigate the influence of horizontal reinforcement above and below the vertical wall segments on the shear strength. Experimental observations and the comparison between the measured strength and the predicted values of ACI 318-14 code are reported. Besides, this research proposes the Softened Strut-and-Tie model to predict the shear strength of RC wall with openings.