考虑单侧翼缘受载腹板屈曲的不锈钢钢管设计

Design of Stainless Steel Tubular Sections Subjected to Web Crippling under One-Flange Loading

本文给出了冷成型不锈钢方钢管和矩形钢管在腹板屈曲时的设计公式。研究了两种单翼缘加载的情况,一种是端部单翼缘加载,另一种是内部单翼缘加载,此外还研究了内部加载的情况。采用屈服线理论预测了不锈钢管截面的腹板屈曲强度。屈服线理论模型是在试验中观察到的破坏模式的基础上发展起来的。在屈服线模型基础上采用不同的假定,给出了计算冷成型不锈钢方钢管和矩形钢管的腹板屈曲强度的三种设计方法。其中两种腹板屈曲设计方法是完全采用屈服线分析理论推导出来的,另外一种设计方法是综合理论分析和经验分析得到的。将试验得到的腹板屈曲强度和这三种设计方法得到的屈曲强度进行了对比。结果表明采用纯理论推导得到的设计方法计算得到的腹板屈曲设计强度偏于保守,而综合了理论分析和经验分析得到的设计方法其计算的腹板屈曲设计强度值比较合理,可以用于单翼缘受载时冷成型不锈钢管的设计。

Design equations of cold formed stainless steel square and rectangular hollow sections subjected to web crippling are proposed in this paper. The one flange loading conditions of End One-Flange and Interior-One-Flange as well as interi-or loading condition have been investigated. The web crippling strengths of stainless steel tubular sections were pre-dicted using the yield line mechanism method. The yield line mechanism model was developed based on the failure mode observed from tests. Three design procedures to predict the web crippling strengths of cold-formed stainless steel square and rectangular hollow sections based on the yield line model using different assumptions have been con-sidered. Two of the web crippling design procedures were purely derived from theoretical analysis using yield line mechanism, and one design procedure was derived through a combination of theoretical and empirical analyses. The web crippling test strengths were compared with the design strengths obtained using the three design procedures. It is shown that the web crippling design strengths calculated using the design procedures purely derived from theoretical analysis were generally conservative, while the proposed web crippling design equations that derived through a combi- nation of theoretical and empirical analyses were generally less conservative and reliable for cold-formed stainless steel tubular sections under one-flange loading.