This paper is concerned with the behaviour of concrete-filled tubular flange girders (CFTFGs) under the combination of bending and tensile axial force. CFTFG is a relatively new structural solution comprising a steel beam in which the compression flange plate is replaced with a concrete-filled hollow section to create an efficient and effective load-carrying solution. These members have very high torsional stiffness and lateral torsional buckling strength in comparison with conventional steel I-girders of similar depth, width and steel weight and are there-fore capable of carrying very heavy loads over long spans. Current design codes do not explicitly include guidance for the design of these members, which are asymmetric in nature under the combined effects of tension and bending. The current paper presents a numerical study into the behaviour of CFTFGs under the combined effects of positive bending and axial tension. The study includes different loading combinations and the associated failure modes are identified and discussed. To facilitate this study, a finite element (FE) model is developed using the ABAQUS software which is capable of capturing both the geometric and material nonlinearities of the behaviour. Based on the results of finite element analysis, the moment–axial force interaction relationship is presented and a simplified equation is proposed for the design of CFTFGs under combined bending and tensile axial force.

本文关注的是在弯曲和轴向拉伸力共同作用下的钢管混凝土翼缘梁（CFTFGs）的性能。CFTFG是一种相对较新的结构解决方案，包括钢梁，其中，将压缩法兰板替换为填充混凝土的空心部分，以创建高效有效的承载解决方案。与具有相似深度，宽度和钢重量的常规钢工字钢相比，这些构件具有非常高的扭转刚度和横向扭转屈曲强度，因此能够在很长的时间内承受非常重的载荷。当前的设计规范未明确包括这些构件的设计指南，这些构件在受拉和弯曲的共同作用下本质上是不对称的。本文对CFTFG在正向弯曲和轴向拉力共同作用下的行为进行了数值研究。该研究包括不同的载荷组合，并确定并讨论了相关的失效模式。为了促进这项研究，使用ABAQUS软件开发了一个有限元（FE）模型，该模型能够捕获行为的几何和材料非线性。基于有限元分析的结果，给出了弯矩-轴向力相互作用的关系，并提出了在弯曲和拉伸轴向力共同作用下的CFTFG设计的简化方程。为了促进这项研究，使用ABAQUS软件开发了一个有限元（FE）模型，该模型能够捕获行为的几何和材料非线性。基于有限元分析的结果，给出了弯矩-轴向力相互作用的关系，并提出了在弯曲和拉伸轴向力共同作用下的CFTFG设计的简化方程。为了促进这项研究，使用ABAQUS软件开发了一个有限元（FE）模型，该模型能够捕获行为的几何和材料非线性。基于有限元分析的结果，给出了弯矩-轴向力相互作用的关系，并提出了在弯曲和拉伸轴向力共同作用下的CFTFG设计的简化方程。