[提要] 高强冷弯薄壁型钢结构在国外低层住宅和门式刚架体系中应用较广，国内已开始采用，但尚无相应设计规范可依。针对屈服强度550MPa高强钢材冷弯薄壁型钢结构常用的轴压构件的承载力设计方法进行了研究，包括其承载力计算模式及设计可靠度分析，并据此提出了相应的设计方法。最后，通过国内外现有相关试验数据的分析，验证了所提出的强度设计指标及承载力设计方法的合理性与可靠性。
［关键词］ 高强冷弯薄壁型钢结构 轴心受压构件 承载力设计方法 强度设计指标 有效宽厚比
Loadcarrying Capacity Design for Axially Compressed Members of 550MPa  Coldformed Thinwalled Steel Structures/Li Yuanqi 1，Wang Lei 1，Shen Zuyan 1，Wang Yanmin2，Xu Hongwei 3
(1 Dept. of Building Engineering, Tongji University, Shanghai 200092, China; 2 Blue Scope Buildings, Residential, Bluescope Steel Co. Ltd., Shanghai 201603, China; 3 Baoshan Iron & Steel Co., Ltd., Shanghai 201900, China)
Abstract:Highstrength steel coldformed thinwalled sections have been widely used in lowrise residential buildings and portal steel frame structures in developed countries, and come to be used in China.There are no related provisions in design codes in China for reference in engineering practice.The loadcarrying capacity design method for axially compressed members, which are typical in common use in 550MPa highstrength coldformed thinwalled steel structures, is discussed, including the loadcarrying capacity estimation method, design reliability index and design strength values.The reasonable and suitable loadcarrying capacity design method is recommended. Finally, with existing relevant experimental data, the reasonability and reliability of the presented design strength level for 550MPa highstrength coldformed thinwalled structural steels and the loadcarrying capacity design method for their axially compressed members have been established.
Keywords:highstrength coldformed thinwalled section steel structures; axially compressed members; loadcarrying capacity design method; design strength values; effective widthtothickness ratio