铝合金轴心受压构件局部稳定性参数分析  

Parametric Study on Local Buckling of Aluminium Alloy Columns under Uniform Compression

作　　者：常婷[1] 王元清[1] 石永久[1] 郭小良 

机构地区：[1]清华大学土木工程系土木工程安全与耐久教育部重点实验室,北京100084 [2]唐山市元构铝合金建筑系统开发有限公司,河北唐山063000

出　　处：《建筑科学》2014年第1期38-46,共9页Building Science

基　　金：高等学校博士学科点专项科研基金(No.20110002130002和No.20090002110046)

摘　　要：为研究铝合金轴心受压构件的局部稳定性能,采用有限元软件ANSYS对132个十字形截面、144个箱形截面及180个工形截面进行数值分析。研究板件厚度、局部几何初始缺陷、整体几何初始缺陷、屈服强度、Ramberg-Osgood模型中应变硬化指数n的取值以及板件间相互作用对3类构件屈曲后性能的影响,给出板件全部有效的最大宽厚比[b/t]及有效厚度折减系数αt。分析结果表明:局部几何初始缺陷和屈服强度对[b/t]及αt影响较大,在工程实际中必须考虑;n值主要影响[b/t],对αt的影响不大;板件厚度和整体几何初始缺陷对两者没有影响;工形截面翼缘和腹板间存在相互作用,使两者αt差值减小。在实际工程中,要控制板件的局部几何初始缺陷大小,至少为规范中的普通级;当材性未知时,可取n=f0.2/10,且在该值的±50%之内,n的取值对板件的有效厚度折减系数基本没有影响。In order to study the local buckling behavior of aluminium alloy columns under unflorm compression, finite element analysis of 132 cruciform sections, 144 square-hollow sections and 180 1 sections are carried out by ANSYS. The influence of plate thickness, local initial geometric imperfections, overall initial geometric imperfections, yield strength, the value of strain-hardening exponent n from Ramberg-Osgood model and interaction between adjacent members are studied. The limiting width-thickness ratio [ b/t ] and reduction factor of effective thickness cq are given. The results show that local initial geometric imperfections and yield strength have a remarkable influence on [ b/t ] and c^t, which must be considered ; n effects mainly on [ b/t ] of reinforced plate and little on a~; plate thickness and overall initial geometric imperfections have no influence on both of them; interaction between flange and web of I sections makes the difference between reduction factor of them decrease. Therefore, local initial geometric imperfections must be limited; n can be taken as f0.2/10 if unknown and within ± 50% of this value, the value of n effects little on reduction factor of effective thickness.

关 键 词：铝合金轴心受压构件 局部稳定性 有限元分析 参数分析 

分 类 号：TU395[建筑科学—结构工程]