不同箍筋型式對低強度與普通強度混凝土柱圍束效應之研究

Investigation on Confinement Effectiveness of Low and Normal Strength RC Column with Different Configuration of Transverse Reinforcement

江振堂(Chen-tang Chiang)

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

台灣目前正在進行國中、小學校老舊校舍的補強作業，但是卻發現，早期建築有許多不符合規範設計，這些將會影響結構物之承重能力及行為，本研究將針對這些影響因素進行實驗與分析，並希望能提供後人在進行補強設計時，一個參考的方向。
本研究製作14組250mm X 250mm X 800mm長之低強度與普通強度混凝土柱試體，並進行單向軸壓實驗，其中變因為不同箍筋型式以及混凝土強度。試驗主要是量測混凝土以及鋼筋應變，並繪製成應力應變圖，來探討混凝土的行為，並觀察破壞情形。
實驗結果顯示，箍筋型式未符合規範之試體表現較差，而混凝土強度較低之試體，強度與勁度較一般強度混凝土柱差，但相同狀況之圍束筋卻能顯示較好之圍束效率。

關鍵字

箍筋 ； 繫筋 ； 保護層切口 ； 低強度 ； 圍束效應 ； 鋼筋混凝土

並列摘要

Recently, many retrofitting of school RC buildings are
underway. For seismic resistance of these old buildings, we found many structures were not conforming to the seismic code, and will influence the seismic performance of structures. In the study, the investigation will be focused on the behavior of these RC columns constructed according to as-built structures by means of experiments.
Fourteen short column specimens were manufactured and
subjected to monotonically axial loading. The variables for these specimens are the configuration of transverse reinforcement, tie-up method of crossties, concrete strength, and cover chipping. Deformations of concrete and tie bars were measured electronically, and the crack patterns and failure mode were observed.
Main results showed that specimens which are not designed to the standard code performed worse seismic resistance.

並列關鍵字

cover chipping ； Low Strength ； Crossties ； Transverse Reinforcement ； Confinement Effectiveness ； Reinforced Concrete

參考文獻

“Theoretical Stress-Strain Model for Confined

Concrete,” Journal of Structural Engineering, Vol.

“Behavior of Laterally Reinforced Concrete

Vol. 97, No. ST2, pp. 587-602, February, 1971.

“Observed Stress-Strain Behavior of Confined