非標準箍筋配置之低強度混凝土柱耐震行為探討

Experimental study on reinforced concrete columns with low-strength concrete and substandard transverse hoops

謝延浩(Yen-hao Hsieh)

指導教授 ： 王勇智

國立中央大學/工學院/土木工程學系/碩士(2011年)

摘要

本實驗共製作四支柱試體，實驗試體包含一根符合現行規範配筋之柱試體，而其他三根為有缺失之柱試體，其缺失為低強度混凝土、箍筋形式與箍筋間距。四根試體主要模擬低矮樓房之耐震行為，藉此觀察RC柱受側向力作用時的強度、韌性發展、裂縫的發展情形、與破壞形式。
由實驗結果顯示，根據規範相關規定施做設計的試體，於塑鉸區有緊密箍筋圍束，能有效仰制柱底剪力變形，以致於有良好韌性發展。對於設置箍筋形式與箍筋間距缺失之柱試體，由於會產生柱底剪力破壞。而使用低強度混凝土之柱試體，混凝土無法提供主筋有效握裹，所以最後產生主筋握裹破壞行為。

關鍵字

耐震行為 ； 剪力 ； 鋼筋混凝土柱 ； 低強度混凝土 ； 箍筋 ； 塑性鉸

並列摘要

Four RC columns were tested in the study. One of columns was designed to a ductile behavior specified with ACI code provision. Others were non-ductile columns which simulated their substandard design in concrete strength and transverse hoops. The purpose of this study is to observe the seismic behaviors of test units.
From the test results, the standard specimen, having close transverse reinforcement inside the column, performed a ductile behavior. For the specimens with poor hoop configuration and lose tie spacing, they failed in a brittle manner. The strength decreased rapidly and shear failure was observed in the column hinge zone. For RC columns with low-strength concrete, the bond failure mode of longitudinal reinforcement occur because such low concrete strength can not provide sufficient bond strength for longitudinal reinforcement.

並列關鍵字

plastic hinge ； low-strength concrete ； RC column ； shear ； seismic resistance hoops

參考文獻

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