轴压下三面受火中空钢管混凝土叠合长柱耐火性能研究  

Research on Fire Resistance of Hollow Concrete-encased CFST Long Column Subjected to Three-side Fire and Axial Compression

作　　者：张波 徐光朋 任庆新[1,3] 秦笑笑 ZHANG Bo;XU Guangpeng;REN Qingxin;QIN Xiaoxiao(School of Civil Engineering,Shenyang Jianzhu University,Shenyang,China,110168;Liaoning Qingchuang High-tech Building Industrialization Consulting Co.Ltd.Shenyang,China,110179;School of Transportation,Civil Engineering&Architecture,Foshan University,Foshan,China,528225)

机构地区：[1]沈阳建筑大学土木工程学院,辽宁沈阳110168 [2]辽宁清创高科建筑工业化咨询有限公司,辽宁沈阳110179 [3]佛山科学技术学院交通与土木建筑学院,广东佛山528225

出　　处：《沈阳建筑大学学报（自然科学版）》2023年第4期615-623,共9页Journal of Shenyang Jianzhu University：Natural Science

基　　金：国家自然科学基金项目(51808351);沈阳市科学技术计划项目(21-108-9-34)。

摘　　要：目的解析轴压下三面受火的中空钢管混凝土叠合长柱的力学行为,建议耐火极限简化计算公式。方法采用有限元分析软件ABAQUS建立轴压下三面受火中空钢管混凝土叠合长柱温度场和力学分析模型,研究轴压下三面受火中空钢管混凝土叠合长柱的温度场分布、破坏模态、变形特点、内力分布等,分析空心率、截面边长、荷载比和长细比对中空钢筋混凝土柱耐火极限的影响。结果在高温下中空钢管混凝土叠合长柱发生了内力重分布;截面边长由300 mm分别增加至600 mm、900 mm和1200 mm时,构件耐火极限分别增长了131.83%、221.81%和312.02%;长细比由22增加至44和66时,构件耐火极限分别降低了25.46%和62.77%;荷载比由0.4分别增加至0.5、0.6和0.7时,构件耐火极限分别降低了39.03%、65.71%和85.54%。结论中空钢管混凝土叠合柱的耐火性能优于中空钢筋混凝土柱,提出的耐火极限简化计算公式与有限元模型计算结果吻合程度较好。Analysis of the mechanical behaviour of a hollow concrete-encased CFST long column subjected to a three-sided fire and axial compression,with a proposed simplified formula for calculating the fire resistance limit.The finite element analysis software ABAQUS is used to establish the temperature field and the mechanical finite element analysis model of the hollow concrete-encased CFST long column subjected to three-sided fire and axial compression,to study the temperature field distribution,damage modalities,deformation characteristics and internal force distribution,and to analyse the effects of hollow ratio,section edge length,load ratio and length to slenderness ratio on the fire resistance limit of hollow reinforced concrete columns.The internal force redistribution occurs in long hollow steel tube concrete composite columns at high temperatures;the fire resistance limit of the members increases by 131.83%,221.81% and 312.02% when the section side length is increased from 300 mm to 600 mm,900 mm and 1200 mm,respectively;the fire resistance limit of the members decreases by 25.46%and 62.77%when the length to slenderness ratio is increased from 22 to 44 and 66,respectively.When the loading ratio was increased from 0.4 to 0.5,0.6 and 0.7,the fire resistance limits of the members were reduced by 39.03%,65.71%and 85.54%respectively.Conclusion The fire resistance of hollow concrete-encased CFST columns is better than that of hollow reinforced concrete columns,and the proposed simplified formula for calculating the fire resistance limit agrees well with the finite element model calculation results.

关 键 词：轴压 三面受火 中空钢管混凝土叠合长柱 有限元分析 耐火性能 

分 类 号：TU398.9[建筑科学—结构工程]