轴心受压冷弯薄壁等肢角钢屈曲承载力试验与设计方法研究  

Experiment and design method of buckling capacity of cold-formed thin-walled equal leg angle steel under axial compression

作　　者：姚行友[1,2] 胡成立 谢度宇 陈厚 阮楚航 余黎鹏 杨嘉宝 郭彦利 程娇龙 YAO Xingyou;HU Chengli;XIE Duyu;CHEN Hou;RUAN Chuhang;YU Lipeng;YANG Jiabao;GUO Yanli;CHENG Jiaolong(School of Civil and Architectural Engineering;Jiangxi Province Key Laboratory of Hydraulic&Civil Engineering Infrastructure Security,Nanchang Institute of Technology,Nanchang 330099,China)

机构地区：[1]南昌工程学院土木与建筑工程学院,江西南昌330099 [2]南昌工程学院江西省水利土木工程基础设施安全重点实验室,江西南昌330099

出　　处：《南昌工程学院学报》2023年第6期44-51,共8页Journal of Nanchang Institute of Technology

基　　金：国家自然科学基金资助项目(51868049)。

摘　　要：为研究轴心受压冷弯薄壁等肢角钢屈曲性能和承载力设计方法,对32根不同截面和长细比的等肢角钢进行了轴压承载力试验。试验结果表明,冷弯薄壁等肢角钢轴压长柱试件发生弱轴弯曲屈曲,中长柱和短柱试件主要发生局部屈曲和强轴弯曲屈曲,且表现出较好局部屈曲后强度。采用ABAQUS有限元软件对试验试件进行了模拟,屈曲模式和承载力分析结果与试验结果吻合良好,表明采用有限元模型分析此类等肢角钢屈曲和承载力是可行的。进而采用有限元模型对轴心受压等肢角钢进行了参数化分析,发现长细比越大,构件极限承载力越小;随着宽厚比的增大,极限承载力增长减缓;随着钢材屈服强度的提高,构件极限承载力与屈服承载力比值增大不明显。将试验结果与直接强度法计算结果进行对比,发现采用直接强度法计算角钢承载力偏于保守。最后基于试验和数值分析结果提出轴心受压冷弯薄壁等肢角钢构件承载力计算的直接强度法修正公式,试验结果表明修正公式可行。In order to study the buckling performance and bearing capacity design method of cold-formed thin-walled equal leg angle steel under axial compression,axial compression bearing capacity tests were conducted with 32 equal leg angle steels with different cross-sections and slenderness ratios.The experimental results show that the cold-formed thin-walled equal leg angle steel under axial compression long column specimens dispalys weak axial bending buckling,while the medium long and short column specimens mainly display local and strong axial bending buckling,and have good local post buckling strength.The ABAQUS finite element software was used to simulate the experimental specimens,and the buckling mode and bearing capacity analysis results were consistent with the experimental results,indicating that using the established finite element model to analyze the buckling and bearing capacity of such equal leg angle steel is feasible.Furthermore,a validated finite element model was used for parameterized analysis of axially compressed equal leg angle steel,and it was found that the larger the slenderness ratio,the smaller the ultimate bearing capacity of the component;As the width to thickness ratio increases,the growth of ultimate bearing capacity slows down;As the yield strength of steel increases,the ratio of ultimate bearing capacity to yield bearing capacity of components does not increase significantly.Comparing the experimental results with the direct strength method calculation results,we find that using the direct strength method to calculate the bearing capacity of angle steel is more conservative.Finally,based on experimental and numerical analysis results,a direct strength method correction formula for calculating the bearing capacity of cold-formed thin-walled equal leg angle steel members under axial compression is proposed.The experimental results show that the correction formula is feasible.

关 键 词：冷弯薄壁等肢角钢 轴压构件 弯曲屈曲 局部屈曲 直接强度法 

分 类 号：TU392.1[建筑科学—结构工程]