高温喷水冷却后钢管混凝土柱轴压性能及剩余承载力评估  

Test on axial compression performance and residual bearing capacity assessment of concrete filled steel tube after elevated high temperature and cooling by spray water

作　　者：吴逸冲 贾恒瑞 陈宗平[1,2] 谢旺军 WU Yichong;JIA Hengrui;CHEN Zongping;XIE Wangjun(Colleg of Civil Engineering and Architecture,Guangxi University,Nanning 530004,China;Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education,Nanning 530004,China;Guangxi Vocational and Technical College,Nanning 530023,China)

机构地区：[1]广西大学土木建筑工程学院,广西南宁530004 [2]工程防灾与结构安全教育部重点实验室,广西南宁530004 [3]广西交通职业技术学院,广西南宁530023

出　　处：《混凝土》2023年第4期21-28,共8页Concrete

基　　金：国家自然科学基金(51578163);广西八桂学者专项研究项目([2019]79号);广西科技基地与人才专项(桂科AD21075031)。

摘　　要：为了研究历经火灾高温和喷水冷却后钢管混凝土的轴压性能及其剩余承载力评估方法,以混凝土强度等级、历经最高温度、径厚比、冷却方式为变化参数,设计并完成了24根钢管混凝土试件经历高温冷却后的轴压力学性能试验。观察了试件的轴压破坏过程及形态,获取了相应的荷载-位移曲线,并分析了各变化参数对其轴压性能的影响规律。结果表明:随历经温度的升高,试件的峰值应力和轴压刚度整体呈下降趋势,延性随温度的升高呈现先增大后减小的变化趋势,轴压耗能能力则呈相反趋势;随着混凝土强度等级的提高,峰值应力和轴压刚度逐渐增大,延性则先增后减;增大钢管的径厚比可以大幅提高试件的轴压刚度及延性;与自然冷却相比,喷水冷却试件具有更好的延性及耗能能力;提出了相应的轴压承载力计算式,可以较好地评估钢管混凝土经历高温喷水冷却后的剩余承载力。In order to study the axial compression performance and post disaster evaluation method of concrete-filled steel tube(CFST)after exposure to high temperature and water cooling,based on the parameters which were concrete strength,temperature,diameter thickness ratio and cooling method,24 CFST short columns are designed for axial compressions test after exposure to different high temperatures cooling.The failure process and morphology of the specimens were observed,the load-displacement curves of specimens under axial compression are obtain,and the influence of various parameters on the mechanical behavior of specimens under axial compression were analyzed.The results show that with the increase of temperature,the peak stress and axial compression stiffness of the specimens decrease,the ductility first increases and then decreases with the increase of temperature,while the axial compression energy dissipation capacity shows the opposite trend.With the increase of concrete strength,the peak stress and axial compression stiffness increase gradually and the ductility increases first and then decreases.The axial compression stiffness and ductility of the specimens can be greatly improved by increasing the diameter thickness ratio of steel pipes.Compared with natural cooling,the water cooling test piece has better ductility and energy consumption capacity.The corresponding formula of axial bearing capacity is proposed,which can better evaluate the residual bearing capacity of concrete-filled steel tube after high temperature water spray cooling.

关 键 词：高温后 喷水冷却 钢管混凝土 轴压性能 剩余承载力评估 

分 类 号：TU528.571[建筑科学—建筑技术科学]