The Effectiveness of Combined Ties on the Confinement of Encased Concrete-Filled Steel Box Columns

• Main Authors: Yu-lin - Hsu, 許瑜麟
• Other Authors: Cheng-Cheng Chen
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/dm3s3d

碩士 === 國立臺灣科技大學 === 營建工程系 === 105 === 　　Previous short column tests show that the so-called combined tie is able to provide noticeable confinement to the outskirt concrete. in this study, encased concrete-filled steel box column specimens are tested under prescribed cyclic loading to investigate the effectiveness of the combined tie on the ductility of the encased concrete-filled box columns. Width-to-thickness ratio is the main parameter in this study, base on the test results, the ratio is proposed to be smaller than 37: 　　Elastic analysis results shows that: (1) In the elastic region, the stiffness of the combined ties is related to the width-to-thickness ratio. 　　Experimental results shows that: (1) Combined tie is effective to be used in the design.(2) In providing confinement to concrete, the combined tie has a similar function to the tie used in the reference specimen. (3) In this experiment, the ductility of concrete-filled steel box columns is not significantly affected by the width-to-thickness ratio. (4) For a conservative design, the diameter of supplementary longitudinal reinforcement must not be smaller than 1/6 times the hoop spacing.