不同长径比圆钢管约束钢筋混凝土柱轴压承载力研究  

Axial load behavior of circular tubed reinforced concrete columnswith different length-to-diameter ratios

作　　者：周绪红[1,2,3] 闫标 刘界鹏[3] 甘丹[3] ZHOU Xuhong;YAN Biao;LIU Jiepeng;GAN Dan(Key Laboratory of Mechanics on Disaster and Environment in Western China of the Ministry of Education,Lanzhou University,Lanzhou 730000,China;School of Civil Engineering and Mechanics,Lanzhou University,Lanzhou 730000,China;College of Civil Engineering,Chongqing University,Chongqing 400044,China)

机构地区：[1]兰州大学西部灾害与环境力学教育部重点实验室,甘肃兰州730000 [2]兰州大学土木工程与力学学院 重庆大学土木工程学院,甘肃兰州730000 [3]重庆大学土木工程学院,重庆400044

出　　处：《建筑结构学报》2018年第12期11-21,共11页Journal of Building Structures

基　　金：国家自然科学基金项目(51438001,51622802)

摘　　要：与钢管混凝土柱不同,钢管约束钢筋混凝土柱的外包钢管主要用于约束核心混凝土而非承担纵向荷载。相比方形截面柱,圆形截面柱的钢管可为混凝土提供更强的约束,使得圆钢管约束混凝土柱具有更高的承载力和更好的延性。以柱长径比（L/D）、钢管径厚比（D/t）为变化参数,对10根圆钢管约束钢筋混凝土柱的轴压力学性能进行试验研究,并对各试件的破坏模式、承载力及荷载-钢管应力曲线进行对比分析。结果表明：钢管的强约束性仅适用于短柱情况,钢管与混凝土间的黏结摩擦和构件较长导致的稳定问题都会限制钢管约束作用的发挥。在试验研究的基础上,根据有限元参数分析结果,对现有国内外规范中相关计算公式的适用性进行了验证,并建立了考虑钢管约束作用随构件长细比增大而降低的轴压稳定承载力计算式。Unlike concrete filled steel tube column, the tubed remlorced concrete （TRC） commn is a composuc column in which the outer steel tube is mainly used to provide confinement to the core concrete. Compared with square TRC column, the steel tube of circular TRC column can provide more pronounced confinement to the core concrete, and thus shows higher ultimate strength and better ductility. A total of ten circular TRC columns were tested to investigate the effects of length-to-diameter ratio （ L/D ） of the specimens and diameter-to-thickness ratio （ D/t ） of the steel tubes. The failure mode, ultimate strength and load-tube stress response of each specimen were summarized and analyzed. The test results indicate that the strong confinement of steel tube is only applicable for short columns. For slender columns, the confinement effect of steel tube cannot be sufficiently utilized due to the bond, friction between the steel tube and the concrete core, as well as the instability of the columns due to their slender nature. Parametric studies were performed based on the test results, and the feasibility of existing design codes has also been verified. Finally, a method for calculating the ultimate strength of this composite column was proposed, in which the effect of column slenderness on tube confinement was taken into account.

关 键 词：圆钢管约束钢筋混凝土 长径比 轴压试验 有限元分析 承载力 柱子曲线 

分 类 号：TU398.903[建筑科学—结构工程]