建筑结构学报2024，Vol.45Issue(2)：52-62,11.DOI:10.14006/j.jzjgxb.2022.0470
四周受火异形截面部分包覆钢-混凝土轴压组合柱耐火性能试验研究
Experimental study on fire resistance of axial-loaded special-shaped partially encased steel-concrete composite column subjected to fire on all sides
摘要
Abstract
Special-shaped partially encased composite steel and concrete(PEC)columns is one of the effective solutions to solve the convex column problem of high-rise steel residential buildings.Due to the exposed steel flanges,its fire resistance has attracted much attention.In order to explore the fire resistance of special-shaped PEC columns,four special-shaped PEC columns were designed and fabricated with different cross-section shapes and axial compression ratios,and the fire tests with constant axial load were carried out.The failure mode,vertical and lateral deformation-time curves and fire resistance of special-shaped PEC columns under fire were obtained,and the temperature field distribution and deformation modes were analyzed.The results show that with the damage evolution under fire,L-shaped and T-shaped PEC columns gradually change from axial compression to bidirectional and unidirectional eccentric compression,respectively,while the cross-shaped PEC columns still maintain axial compression.Under the boundary conditions of the upper spherical hinge and the lower unidirectional hinge,the L-shaped PEC column fails in the bidirectional flexural buckling,the T-shaped PEC column fails in the out-of-plane flexural buckling,and the cross-shaped PEC column fails in the in-plane flexural buckling.Under the axial compression ratio of 0.4,the fire resistance of L-shaped PEC column without fire protection reaches 41 min,the fire resistances of T-shaped and cross-shaped PEC columns are 32.5 min and 29 min,respectively.When the axial compression ratio increases from 0.4 to 0.55,the fire resistance of the cross-shaped PEC column decreases by 28.7％.It is found that the simplified bearing capacity calculation method of regular cross-section PEC columns subjected to fire on all sides recommended in EN 1994-1-2 is conservative to predict the bearing capacity of special-shaped PEC columns at fire resistance.关键词
部分包覆钢-混凝土组合柱/异形截面/火灾试验/耐火性能/高温承载力Key words
partially encased composite steel and concrete column/special-shaped/fire test/fire resistance/bearing capacity in fire分类
建筑与水利引用本文复制引用
杨欢,刘用,王静峰,徐秋雨..四周受火异形截面部分包覆钢-混凝土轴压组合柱耐火性能试验研究[J].建筑结构学报,2024,45(2):52-62,11.基金项目
国家自然科学基金项目(52108130),安徽省自然科学基金项目(2108085QE248),中央高校基本科研业务费专项资金(JZ2021HGTA0158,PA2021GDSK0078). （52108130）
