Despite substantial progress in recent years to improve the design guidance for high strength steel (HSS) structural elements, this has mainly been for ambient conditions with their fire response still in need of further research. Accordingly, this paper reports on an investigation into the structural performance of unprotected HSS hollow section columns in fire. Finite element models of columns made from square, circular and rectangular hollow sections are developed and are validated against test data at ambient and elevated temperature. The validated models are employed to perform parametric studies to assess the influence of a range of variables such as the grades of HSS, levels of temperature exposure and cross-sectional geometry. The structural fire design resistance method for a column given in the Eurocode is assessed based on the FE results. Consequently, new buckling curves are proposed, which provide a more accurate prediction of the real capacity and reliability analysis is also performed on the new proposed design formulations.

尽管近年来在改善高强度钢（HSS）结构元件的设计指南方面取得了重大进展，但这主要是针对环境条件，其火灾响应仍需要进一步研究。因此，本文报道了对未保护的HSS空心截面柱在火灾中的结构性能的研究。开发了由方形，圆形和矩形空心截面制成的圆柱的有限元模型，并针对环境温度和高温下的测试数据进行了验证。经过验证的模型用于进行参数研究，以评估一系列变量的影响，例如HSS的等级，温度暴露水平和截面几何形状。根据有限元分析结果，评估了欧洲规范中给出的圆柱结构耐火设计方法。因此，提出了新的屈曲曲线，该曲线提供了对实际容量的更准确的预测，并且还对新提出的设计公式进行了可靠性分析。