摘要
在合理地选择材料本构模型和接触模型并考虑材料和几何非线性的基础上,建立了带球冠形脱空缺陷的钢管混凝土受弯构件的有限元模型,并利用试验结果验证了有限元模型的可靠性。利用数值模型对带脱空缺陷的钢管混凝土构件在纯弯作用下的全过程工作机理进行了细致剖析,明晰了球冠形脱空缺陷对构件抗弯性能的影响机理。结果表明球冠形脱空缺陷的存在降低了钢管对混凝土的约束效应,使混凝土开裂严重以及加剧了钢管的局部屈曲从而降低了构件的抗弯承载力。基于以上分析,研究了影响约束效应的相关参数对带缺陷的钢管混凝土构件的抗弯承载力以及弯矩-挠度关系曲线的影响规律,并在此基础上提出了考虑脱空缺陷影响的钢管混凝土抗弯极限承载力的简化计算公式,可为相关工程实践提供参考。
A finite element analysis（ FEA） model of concrete filled steel tubular（ CFST） members with spherical-cap gap under bending is built in this paper. The material model and contact model are carefully selected,and both material and geometric nonlinearity are accounted. The FEA model is validated against previous test data. A behavior analysis is performed to study the effect of gap on the CFST members under bending. The results show that the gap reduces the confinement effect between outer tube and core concrete,and thus the cracking of core concrete becomes more severe and the local buckling of outer tube is intensified. Therefore,the bending moment capacity decreases. A series of parametric studies is also conducted utilizing the above model to investigate critical factors influencing bending moment capacity and moment versus deflection response of CFST members with spherical-cap gap. Based on the parametric study results,a simplified calculation equation for predicting the ultimate moment of CFST beams with gap is proposed to provide reference for the practical engineering.
作者
韩浩
廖飞宇
周翔
李永进
HAN Hao;LIAO Feiyu;ZHOU Xiang;LI Yongjin(College of Transportation and Civil Engineering, Fujian Agriculture and Forestry University, Fuzhou 350002, China;Fujian Academy of Building Research, Fuzhou 350025, China)
出处
《建筑钢结构进展》
CSCD
北大核心
2018年第2期67-73,102,共8页
Progress in Steel Building Structures
基金
国家自然科学基金(51578154
51308121)
福建省财政厅科技专项资助项目(K81600002)
关键词
球冠形脱空缺陷
钢管混凝土
抗弯性能
有限元模型
参数分析
简化计算公式
spherical-cap gap
concrete filled steel tube （CFST）
flexural behavior
finite element model
parametric analysis
simplified calculation equation
