建筑结构学报2018，Vol.39Issue(5)：76-83,8.DOI:10.14006/j.jzjgxb.2018.05.010
大长细比约束圆钢管杆件高温承载力试验研究
Experimental study on fire resistance of axially restrained steel chords with large slenderness ratio at elevated temperature
摘要
Abstract
Restrained member characteristics of elements in grid structures were shown obviously when they were exposed to localized fires. Steel chords are the most common type of members in grid structures. In order to study the mechanical behaviors of restrained steel chords in grid structures under fire,a spring sets was designed to provide the constant axial restraint to the pin supports of the chords. And then,a series of fire tests of restrained steel chords with large slenderness ratios were conducted under multiple parameters. The results show that as the load ratio is doubled, the buckling temperature of the specimen drops 90 ℃,and the resistance at buckling stage increases by 18％,and the resistance at post-buckling stage increases to some degree. With the increase of axially restrained stiffness ratio by 77％,the buckling temperature drops 90 ℃, and the resistance at buckling stage increases by 7％,and the axial force jumping at buckling stage and the residual deformation after fire decreases obviously. With the increase of slenderness ratio by 29.3％,the buckling temperature drops 124 ℃,and the resistance at buckling stage decreases by 40％,and the resistance at post-buckling stage increases to some degree. With the increase of initial imperfection,the buckling temperature increases and the resistance at buckling stage decreases slightly. The axial force curves in fire tests fit well with analytical solutions of axially restrained steel chords under fire. The tests results verify the analytical method effectively and specified that the jumping phenomenon of axial force in analytical solutions has proximity.关键词
轴向约束圆钢管/大长细比/组合弹簧装置/受火试验/高温承载力Key words
axially restrained steel chord/large slenderness ratio/spring sets/fire test/fire resistance分类
建筑与水利引用本文复制引用
成飞,杜咏,张永振..大长细比约束圆钢管杆件高温承载力试验研究[J].建筑结构学报,2018,39(5):76-83,8.基金项目
国家自然科学基金项目(51378259),江苏省住房和城乡建设厅科技项目(2014JH13). （51378259）
