Abstract Eurocode EN 1994-1-1 currently covers design of concrete-filled steel tubular (CFST) columns using normal strength materials with nominal steel yield strength (fy) not more than 460 MPa and concrete characteristic cylinder strength less than 50 MPa. As high strength materials have been increasingly used in construction, this paper aims to extend current design equation for square and rectangular CFSTs in EN 1994-1-1 to incorporate high strength materials. A comprehensive experimental database consisting of 443 square and rectangular CFST stub column test results was developed. Statistical evaluations were undertaken and the results indicate that the current cross-section slenderness limit for square and rectangular CFSTs is too conservative and can be safely relaxed from 52 235 / f y to 68 235 / f y . The design equation could be extended to incorporate high strength materials). Then, a reliability analysis in accordance with EN 1990 was performed to evaluate the applicability of the proposed design method. It was found that the current partial factors are safe for the design of square and rectangular CFSTs with normal strength materials even after relaxation of the cross-section slenderness limit. However, modification should be applied to the existing design equation for the design of high strength materials to yield an acceptable safety level. Finally, an experimental investigation on 10 stub column tests was carried out to further verify the applicability of the proposed design recommendation. It was found that the proposed design recommendation yields satisfactory predictions when compared to test results.

中文翻译：

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方形和矩形 CFST 横截面受压能力的设计

摘要 欧洲规范 EN 1994-1-1 目前涵盖了使用普通强度材料的钢管混凝土 (CFST) 柱的设计，其公称钢屈服强度 (fy) 不超过 460 MPa，混凝土特征圆柱强度小于 50 MPa。随着高强度材料越来越多地用于建筑，本文旨在扩展 EN 1994-1-1 中方形和矩形 CFST 的当前设计方程，以纳入高强度材料。开发了一个由 443 个方形和矩形 CFST 短柱测试结果组成的综合实验数据库。进行了统计评估，结果表明，目前方形和矩形 CFST 的横截面细长限制过于保守，可以安全地从 52 235 / fy 放宽到 68 235 / fy 。设计方程可以扩展到包含高强度材料）。然后，根据 EN 1990 进行可靠性分析，以评估所提出的设计方法的适用性。结果表明，即使在放宽横截面细长限制后，当前的部分因素对于具有正常强度材料的方形和矩形 CFST 的设计也是安全的。然而，应修改现有的高强度材料设计方程，以产生可接受的安全水平。最后，对 10 个短柱测试进行了实验研究，以进一步验证所提出的设计建议的适用性。结果发现，与测试结果相比，所提出的设计建议产生了令人满意的预测。