冷弯薄壁型钢四肢组合受弯构件承载力研究  

Analysis of the Bearing Capacity of Cold-formed Steel Quadruple Limbs Built-up Members under Flexural Loading

作　　者：赵一婕[1] 杜兆宇[1,2] 张其林[1] 

机构地区：[1]同济大学土木工程学院,上海200092 [2]上海绿筑住宅系统科技有限公司,上海200233

出　　处：《湖南大学学报（自然科学版）》2012年第11期28-34,共7页Journal of Hunan University:Natural Sciences

基　　金：国家科技支撑计划项目(2008BAJ08b06)

摘　　要：针对冷弯薄壁型钢四肢组合箱形截面受弯构件,建立了考虑材料、几何和接触非线性的有限元模型,进行了其承载力的数值分析.数值分析所得构件的破坏模式、极限承载力和荷载-挠度曲线与试验结果吻合较好,验证了有限元模型的可靠性.采用这一模型就钉距、截面高度、宽度及初始缺陷等对构件极限承载力的影响进行了一系列参数分析.提出了构件实用设计和计算的折减系数法,与现有AISI和中国规范基于有效宽度法的计算结果进行了比较,证明现有规范计算结果偏于保守,本文方法与数值分析结果吻合较好、简便可行.Specimens of cold-formed steel quadruple limbs built-up box section member were tested to investigate its load capacity under flexural loading,and a finite element model involving geometric large deformation,materials and contact nonlinearity was established for numerical analysis.The model was validated by comparing the failure mode,ultimate bearing capacity and load-deflection curves with the test result.Based on this proved model,a series of parametric analysis was carried out to identify factors affecting flexural strength,such as spacing of screws,the height and width of section,and the quantity of initial imperfections.A practical design method named reduction coefficient method based on effective width method was proposed and compared with current AISI and Chinese cold-formed steel codes.It shows that current AISI and Chinese codes lead to a conservative evaluation.The reduction coefficient method proposed in this paper shows good agreement with the finite element result,and is relatively simple and convenient for design.

关 键 词：冷弯薄壁型钢 组合箱形截面 承载力 有限元法 参数分析 有效宽度法 

分 类 号：TU392.5[建筑科学—结构工程]