%0 Journal Article
%T 冷弯薄壁型钢四肢拼合箱形柱轴压性能试验<br>Experiment on cold-formed steel quadruple-limb built-up box section columns under axial compression
%A 聂少锋
%A 周天华
%A 周绪红
%A 霍洋洋
%A 孙玉金
%J 长安大学学报(自然科学版)
%D 2017
%X 为了解冷弯薄壁型钢拼合箱形截面立柱的受力性能，对21根不同长细比的冷弯薄壁型钢单肢C形、U形及四肢拼合箱形截面立柱的轴压受力性能进行了试验研究，获得了试件的极限承载力和荷载？参灰魄？线，分析试件的屈曲模式和破坏特征，并采用《冷弯薄壁型钢结构技术规范》（GB 50018―2002）的有效宽厚比法、北美规范（AISI S100―2007）的有效宽度法、直接强度法及简单叠加法对拼合柱的极限承载力进行了计算和对比分析；采用ABAQUS软件建立了考虑材料、几何和接触非线性的有限元模型，对试验试件的轴压性能进行模拟分析，并将数值分析得到的破坏特征、荷载？仓嵯蛭灰魄？线与试验结果进行对比分析，验证了有限元方法的正确性；进而采用经验证的有限元模型对该类拼合柱轴压性能的影响因素（包括长细比、螺钉间距和腹板高厚比等）进行分析。研究结果表明：单肢中长柱试件破坏模式为局部屈曲和整体弯曲失稳，单肢短柱试件破坏模式为局部屈曲和畸变屈曲；中长拼合柱试件最终破坏模式为绕弱轴整体弯曲，短柱试件破坏模式为局部塑性折曲；拼合柱的极限承载力和刚度随长细比的增大逐渐降低，长细比大于30的箱形柱拼合效果显著，螺钉连接可以满足各肢协同工作的要求，长细比较小的箱形柱拼合效果差；采用简单叠加法计算承载力偏于不安全；减小箱形柱截面的腹板高厚比，其轴压极限承载力和刚度将显著提高。<br>To understand the mechanical properties of cold-formed steel built-up box section columns, the mechanical behaviors of 21 specimens of cold-formed steel single C-shaped, U-shaped and quadruple-limb built-up box section columns with different slenderness ratios were tested under axial compression load. The ultimate capacity and load-displacement curves of specimens were obtained. The flexural mode and failure characteristics were described in detail. The ultimate capacities of built-up specimens were calculated and comparatively analyzed by “effective ratio of width to thickness” in “Technical code of cold-formed thin-wall steel structures” (GB 50018―2002), “effective width method” and “direct strength method (DSM)” in “North American specification for the design of cold-formed steel structural members” (AISI S100―2007) and “simple superposition method”. Finite element models considering materials, geometric and contact nonlinearities were established by finite software ABAQUS to simulate and analyze the mechanical behaviors of the test specimens under axial compression. Furthermore, failure characteristics and load-axial displacement curves obtained by numerical analysis were comparatively analyzed with the experimental results so as to verify the validity of finite element methods. Influencing factors on behaviors of columns under axial compression, including slenderness ratio, spacing of screws and height-thickness ratio of web were analyzed through the proved FEM. The results show that the failure mode of middle and long single columns is local buckling and overall flexural buckling instability, while the failure mode of short single columns is local buckling and distortional buckling. Ultimate failure mode of middle and long built-up columns is overall flexural buckling around the weak axis, while that of the short columns is local plastic cripple. The ultimate bearing capacity and stiffness of built-up columns gradually decrease with the increase of slenderness ratio. For
%K 结构工程
%K 冷弯型钢拼合箱形柱
%K 轴压性能
%K 试验研究
%K 破坏模式
%K 模拟分析&lt
%K br&gt
%K structural engineering
%K cold-formed steel built-up box section column
%K axial compression performance
%K experimental study
%K failure mode
%K simulation analysis
%U http://zzszrb.chd.edu.cn/oa/DArticle.aspx?type=view&id=201509020