双肢冷弯薄壁型钢拼合箱形柱受压试验研究与有限元分析  

Experimental study and numerical analysis on double limb cold-formed steel built-up closed section columns under compression

作　　者：聂少锋[1] 周天华[1] 周绪红[2] 李方涛[1] 孙玉金[1] 

机构地区：[1]长安大学建筑工程学院,陕西西安710061 [2]重庆大学土木工程学院,重庆400044

出　　处：《建筑结构学报》2017年第10期10-20,共11页Journal of Building Structures

基　　金：国家自然科学基金项目(51408052);高等学校博士学科点专项科研基金项目(20110205110006);陕西省工业攻关项目(2014K06-23)

摘　　要：通过30根由双肢C形和[形冷弯薄壁型钢拼合箱形柱的轴压和偏压试验,得到了试件的荷载-位移曲线和最大荷载,并分析了其屈曲模式和破坏特征。采用ABAQUS程序对拼合截面柱受压性能进行了有限元分析,分析参数主要包括长细比、腹板高厚比、截面高宽比、偏心距与偏心方向等。结果表明:轴压中、长柱系列试件的破坏模式为绕弱轴整体弯曲破坏,轴压短柱系列试件为局部屈曲变形过大而导致的塑性折曲,绕强轴和绕弱轴的偏压试件最终分别为整体弯扭屈曲和整体弯曲破坏;试件的最大轴压荷载及刚度均随着试件长细比的增大而逐渐减小;试件最大轴压荷载随腹板高厚比的增大而减小;试件的截面高宽比较大,绕两个主轴的长细比会相差较大,通过增加翼缘宽度以增大拼合柱绕强轴和弱轴的稳定性,显著提高其最大荷载;偏压拼合柱的最大荷载随着偏心距的增加而降低。The 30 specimens of cold-formed steel with C and [ shape member buih-up closed section columns were tested under axial and eccentric compression. The load-displacement curves and maximum load of specimens were obtained. The buckling modes and failure characteristics were analyzed. The ABAQUS was used to simulate the compressive behavior of specimens and analyze the influence factors. The influence parameters included slenderness ratio, height-thickness ratio of web, height-width ratio of section, eccentric distance and eccentric direction on columns. The results show that the failure modes of long-height and mid-height specimens under axial compression are overall buckling around weak axis, while that of short-height specimens are plastic flexure caused by excessive local buckling. Specimens under eccentric compression around strong axis and weak axis are bending torsional buckling and overall buckling respectively. The axial compressive maximum load and stiffness of specimens decrease with the increase of slenderness ratio. With the increase of height-thickness ratio of web, axial compressive maximum load of specimens decreases gradually. The height-width ratios of specimens are big and the slenderness ratios around the two main axes are different greatly, so that the maximum load of specimens can be improved significantly by increasing the flange width as well as to increase the equistability of specimen around strong axis and weak axis. The maximum load of specimens under eccentric compression decreases with the increase of eccentricity.

关 键 词：双肢拼合箱形柱 冷弯薄壁型钢 静力试验 有限元分析 受压性能 

分 类 号：TU392.103[建筑科学—结构工程] TU311.41