摘要
为研究冷弯薄壁型钢异型截面货架立柱在局部火灾下的轴压性能,以欧洲规范EN 1991-1-2和EN 1993-1-2为基础,采用有限元分析软件ABAQUS模拟火源在构件底部时的温度场,并对局部火灾情况下冷弯薄壁型钢货架立柱进行轴压稳定性分析。首先通过现有试验结果验证了有限元分析模型的准确性,随后对不同截面、不同长度和不同厚度的货架立柱在不同温度作用下的轴压性能进行数值分析,并在温度场分析模型中考虑了火焰长度、火焰直径和热释放率等3个因素的影响。结果表明:货架立柱的长度和温度对其轴压承载力有较大影响;在局部火灾情况下,货架立柱温度沿长度方向呈现梯度分布,并且这种温度梯度对货架立柱破坏模式有着重要影响。最后,基于数值参数分析结果,给出了冷弯薄壁型钢货架立柱在局部火灾(800℃)情况下适用于整体屈曲的直接强度法(DSM)设计曲线。
To study the compression behaviour of cold-formed thin-walled steel storage rack uprights with complex sections exposed to localised fires,this study,based on EN 1991-1-2 and EN 1993-1-2,used the finite element software ABAQUS to simulate the temperature field of uprights under localised fires when the fire source was on the bottom of members.The stability analysis on compression uprights under localised fires was carried out.Because the fire source had an important influence on temperature field of uprights,the flame length,diameter and heat release rate of localised fires were considered in finite element analyses(FEA).The developed finite element model was verified against existing experimental data,and then parameter study was conducted,by considering different types of cross-section,multiple lengths,different thicknesses and various temperatures.The results of parametric study show that the main factors affecting the axial strength were the length and temperature of storage rack uprights;and the temperature gradient along the length of storage rack uprights under localised fire had important influence on the failure model of uprights.Based on the results of parametric study,this paper reports a modified direct strength method(DSM)curve(800℃)for cold-formed thin-walled steel storage rack uprights failing in global buckling mode under localised fires.
作者
任重
张鹏
戴柳丝
REN Chong;ZHANG Peng;DAI Liusi(Department of Civil Engineering, Shanghai University, Shanghai 200444, China)
出处
《太原理工大学学报》
CAS
北大核心
2020年第1期35-42,共8页
Journal of Taiyuan University of Technology
基金
国家自然科学青年基金资助项目(51908347)
关键词
局部火灾
冷弯薄壁型钢
破坏模式
轴压承载力
温度梯度
直接强度法
localised fire
cold-formed thin-walled steel
failure mode
axial compression strength
temperature gradient
direct strength method
