摘要
在不锈钢(外)-碳素钢(内)双金属复合管内填入混凝土所形成的双金属复合管混凝土(CFBT)构件,具有良好的受力性能和耐腐蚀性。为研究CFBT构件在低周往复荷载作用下的弯曲滞回性能,开展了3个CFBT试件和1个传统碳素钢管混凝土(CFST)试件的加载试验和有限元模拟,分析不同混凝土强度条件下试件的破坏形态、荷载-变形滞回曲线、骨架曲线、承载力和刚度等受力性能。研究结果表明:往复荷载作用下CFBT受弯构件的变形和破坏特征与CFST受弯构件相似,最终均呈现为底梁附近钢管局部鼓曲、对应位置的内填混凝土压溃破坏;所有构件的弯曲滞回曲线饱满,无明显捏拢和退化现象,表明双金属复合管与内填混凝土能有效共同工作,使整体构件具有良好的承载力和滞回耗能能力;内填混凝土的强度对CFBT构件受弯承载力和滞回性能的影响不显著;在常用金属材料强度范围内,双金属复合管的不锈钢与碳素钢材料厚度比对CFBT受弯构件的受力性能无明显影响;增大碳素钢的强度或提高含钢率可有效提高CFBT受弯构件的受弯承载力。利用现有的CFST受弯构件计算模型可较好预测相同几何和材料参数条件下CFBT构件的受弯承载力。
Concrete-filled stainless steel(outer)-carbon steel(inner)bimetallic tubes(CFBTs)possess favorable mechanical properties and corrosion resistance.To investigate the flexural hysteretic performance of CFBT members under low cyclic reversed lateral loads,three CFBT specimens and one conventional concrete-filled carbon steel tube(CFST)specimen were tested and corresponding finite element analysis was conducted.The failure modes,load-deformation hysteretic curves,skeleton curves,load-carrying capacity,and stiffness of specimens with various concrete strengths were analyzed.The results show that the CFBT specimens have similar deformation and failure characteristics with the CFST counterpart,and all the CFBT and CFST specimens fail in local buckling of the tube near the end,accompanied by crushing of infilled concrete at the corresponding location.The flexural hysteretic curves for all specimens show plump shape without obvious pinching or degradation phenomena,which indicates the bimetallic tube and the infilled concrete could work together,endowing the whole CFBT member with attractive load-carrying and energy-dissipation capacities.The concrete strength has a minor influence on the flexural strength or hysteretic performance of CFBT members.Within the range of normal metal strengths,the stainless steel-carbon steel ratio of the bimetallic tube does not have an obvious influence on the flexural performance of CFBT members.The flexural performance of CFBT members is effectively improved by increasing the strength of carbon steel or the steel ratio.The currently available model for CFST flexural members could be used to predict the flexural strength of CFBT members with the same geometries and material properties.
作者
叶勇
苗伟
张世江
陈香清
YE Yong;MIAO Wei;ZHANG Shijiang;CHEN Xiangqing(College of Civil Engineering,Huaqiao University,Xiamen 361021,China;Key Laboratory for Structural Engineering and Disaster Prevention of Fujian Province,Huaqiao University,Xiamen 361021,China)
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2023年第8期110-119,共10页
Journal of Building Structures
基金
国家自然科学基金项目(51808234,52278182)
福建省自然科学基金项目(2021J01286)。
关键词
双金属复合管混凝土构件
拟静力试验
有限元分析
滞回性能
承载能力
concrete-filled bimetallic tube
pseudo static test
finite element analysis
flexural hysteretic behavior
load-carrying capacity
