往复荷载作用后钢管混凝土柱-组合梁节点耐火性能数值分析  

Numerical investigation of fire resistance of concrete-filled steel tubular column-composite beam joints after cyclic loading

作　　者：王文达[1,2] 李生强 毛文婧 郑龙 WANG Wenda;LI Shengqiang;MAO Wenjing;ZHENG Long(School of Civil Engineering,Lanzhou University of Technology,Lanzhou 730050,Gansu,China;Shanghai Key Laboratory of Engineering Structure Safety,SRIBS,Shanghai 200032,China)

机构地区：[1]兰州理工大学土木工程学院,甘肃兰州730050 [2]上海市建筑科学研究院有限公司上海市工程结构安全重点实验室,上海200032

出　　处：《建筑科学与工程学报》2025年第1期1-13,共13页Journal of Architecture and Civil Engineering

基　　金：甘肃省基础研究创新群体项目(24JRRA169);上海市工程结构安全重点实验室开放课题(2023-KF05)。

摘　　要：为研究钢管混凝土柱-组合梁节点在往复荷载作用后的耐火性能,利用有限元软件ABAQUS建立了该节点的有限元分析模型,并与已有试验结果进行对比验证。在此基础上,分析了往复荷载作用后塑性损伤和残余变形对组合梁节点火灾下的应力和变形的影响,以及不同损伤程度、荷载作用水平和防火保护层厚度对节点耐火极限和破坏模态的影响。结果表明:地震预损伤对节点的耐火极限有不利影响,且随损伤程度的增加,耐火极限下降明显;重度损伤下节点的耐火极限与无损伤节点相比降低了23.5%;重度损伤的节点在火灾作用下形成塑性铰,且产生较大的耗能损伤,轻度和中度损伤下未形成明显塑性铰,耐火极限分别仅下降1.0%和3.6%;对于以梁损伤作为预损伤模式的节点,梁荷载比和防火保护层厚度是影响有地震预损伤节点耐火极限的主要因素;随柱荷载比的增大,耐火极限呈降低趋势,但整体影响不大。To study the fire resistance of concrete-filled steel tubular(CFST)column-composite beam joint after cyclic loading,the finite element model of the joint was developed using ABAQUS software and verified with existing experimental results.On this basis,the influence of plastic damage and residual deformation on the stress and deformation of composite beam joints under fire after cyclic loading was analyzed,and the influence of different damage degree,load level and fire protection layer thickness on the fire resistance limit and failure mode of joints was analyzed.The results show that the seismic pre-damage has an adverse effect on the fire resistance of the joints.The fire resistance has a significant decrease with the increase of the pre-damage degree.The fire resistance limit of the joint with severe damage is reduced by 23.5%compared with the joint without damage.The joints with severe damage form plastic hinges under fire and produce large energy dissipation damage.No obvious plastic hinges are formed under mild and moderate damage,and the fire resistance limit is only reduced by 1.0%and 3.6%,respectively.For joints considering beam damage as the primary pre-damage mode,the beam load ratio and the fire protection layer thickness are the key factors that affect the fire resistance of joints.With the increase of the column load ratio,the fire resistance limit decreases,but the overall effect is not significant.

关 键 词：钢管混凝土柱-组合梁节点 低周往复加载 损伤程度 耐火极限 

分 类 号：TU391[建筑科学—结构工程]