邓露，龙砺芝，刘艳芝，何钰龙

摘   要：冷弯薄壁矩形钢管柱易发生局部屈曲破坏. 为了研究冷弯薄壁矩形钢管柱的压弯承载性能，建立并验证了冷弯薄壁矩形钢管柱非线性有限元模型. 采用上述模型对不同轴压比、翼缘宽厚比及腹板宽厚比的884个受常轴压力、变水平力作用的矩形钢管柱进行参数分析，研究了构件承载极限状态的截面破坏形式和抗弯承载力. 结果表明：冷弯薄壁矩形钢管柱绕强轴压弯过程主要出现两种破坏模式，比如：全截面屈服和受压翼缘与腹板屈曲. 结合极限状态的应力分布特征，基于有效塑性宽度法提出了考虑板组相关屈曲的冷弯薄壁矩形钢管柱的极限抗弯承载力计算公式，其预测值与有限元模拟结果吻合良好.

关键词：板件相关作用;局部屈曲;抗弯承载力;冷弯薄壁;矩形截面钢管柱

中图分类号：TU338                              文献标志码：A

Research on Compression-bending Capacity

of Cold-formed Thin-walled Rectangular Tube Considering

Interactive Buckling of Plate Group

DENG Lu1，2，LONG Lizhi1，LIU Yanzhi1，HE Yulong1

（1. College of Civil Engineering，Hunan University，Changsha 410082，China;

2. Key Laboratory of Building Safety and Energy Efficiency（Hunan University），Ministry of Education，Changsha 410082，China）

Abstract：Cold-formed thin-walled rectangular steel tube columns are prone to local buckling failure. In order to study the compression-bending capacity of cold-formed thin-walled rectangular steel tube columns， a nonlinear finite element model of cold-formed thin-walled rectangular steel tube columns was established and verified. This model is used to simulate 884 rectangular steel tube columns with different axial compression ratios， flange width-thickness ratios， and web width-thickness ratios under constant axial pressure and variable horizontal forces， and the failure mode and flexural capacity in the ultimate limit states are examined. The results show that there are mainly two failure modes in the compression-bending process of cold-formed thin-walled rectangular steel tube columns in the strong axial： full-section yield， and compression flange and web buckling. Combined with the stress distribution characteristics of the limit state，a calculation formula for the ultimate flexural capacity of cold-formed thin-walled rectangular steel tube columns considering the relative buckling of the plate group is proposed based on the plastic effective width method. The predicted value is in good agreement with the finite element simulation results.

Key words：related effects of plates;local buckling;flexural capacity;cold-formed thin-wall;rectangular section steel tube column

冷彎薄壁型钢构件因具有轻质、高强、易装配等优点而被广泛应用于低层建筑，且近年来逐步从低层向多层建筑发展[1]. 因其受压性能好、抗弯刚度较大，冷弯薄壁矩形钢管柱广泛用于多层框架柱结构抗侧力构件. 然而，冷弯薄壁矩形钢管柱的板件宽厚比一般较大，易发生局部屈曲，削弱了构件的极限承载力. 因此，局部屈曲是研究冷弯薄壁型钢构件极限承载性能的重点问题之一.

关于冷弯薄壁型钢板件局部屈曲的问题，国内外研究较为成熟. 多板件组合的冷弯薄壁型钢构件（T形、H形……