The structural behaviour and design of hot-rolled steel square and rectangular hollow sections (SHS and RHS) under combined axial compression and bending are studied in the present paper. Finite element (FE) models were developed and validated against existing experimental results on hot-rolled normal strength and high strength steel SHS and RHS under combined loading. Upon validation against the test results, an extensive parametric study was then performed with the aim of expanding the available structural performance data over a wide range of cross-section geometries, cross-section slendernesses, steel grades and loading scenarios. Both the experimentally and numerically obtained data were utilised for an assessment of the accuracy of the current design rules in European and American standards for hot-rolled steel tubular sections under combined loading. The comparisons revealed that the codified capacity predictions are generally somewhat conservative and scattered, due mainly to the neglect of strain hardening in the case of stocky cross-sections and the rather crude treatment of the partial spread of plasticity for Class 3 (semi-compact) cross-sections. The deformation-based continuous strength method (CSM) has been successfully applied to the design of hot-rolled steel cross-sections under isolated loading conditions (i.e. compression or bending), and shown to provide more accurate and consistent ultimate resistance predictions than the existing design provisions. This paper presents the first study to extend the CSM to the design of hot-rolled steel SHS and RHS, made of both normal and high strength steels, under combined loading, underpinned by both experimentally and numerically derived data points. Advantages of the proposed approach include eliminating the discontinuity in the current codified methods, yielding more accurate and consistent resistance predictions and providing knowledge of the level of strain required to reach a given resistance. The reliability of the proposed method is statistically verified in accordance with EN 1990.

研究了方形和矩形中空热轧钢（SHS和RHS）在轴向压缩和弯曲作用下的结构行为和设计。开发了有限元（FE）模型，并根据组合载荷下热轧法向强度和高强度钢SHS和RHS的现有实验结果进行了验证。根据测试结果进行验证后，随后进行了广泛的参数研究，目的是在广泛的横截面几何形状，横截面细长度，钢种和载荷情况下扩展可用的结构性能数据。实验和数值获得的数据均用于评估组合载荷下欧洲和美国标准的热轧钢管型材中当前设计规则的准确性。比较结果表明，编纂后的容量预测通常较为保守和分散，这主要是由于在横截面过大的情况下忽略了应变硬化以及对3类（半紧凑型）可塑性的部分扩展进行了粗略的处理。交叉区域。基于变形的连续强度方法（CSM）已成功应用于孤立载荷条件下（即压缩或弯曲）的热轧钢截面设计，并且显示出比现有方法更准确，一致的极限抗力预测设计规定。本文提出了第一个将CSM扩展到由普通和高强度钢制成的热轧钢SHS和RHS的设计，这些钢在联合载荷下受到实验和数值推导的数据点的支持。提出的方法的优点包括消除当前编码方法中的不连续性，产生更准确和一致的电阻预测，并提供达到给定电阻所需的应变水平的知识。该方法的可靠性已根据EN 1990进行了统计验证。所提出方法的优点包括消除当前编码方法中的不连续性，产生更准确和一致的电阻预测以及提供达到给定电阻所需的应变水平的知识。该方法的可靠性已根据EN 1990进行了统计验证。提出的方法的优点包括消除当前编码方法中的不连续性，产生更准确和一致的电阻预测，并提供达到给定电阻所需的应变水平的知识。该方法的可靠性已根据EN 1990进行了统计验证。