薄壁钢箱梁的极限强度及有效宽比分析

Strength and Valid Width Ratio Analysis of Thin Walled Steel Box Beam in Limit State

对由线应力性强化材料制造的薄壁钢箱梁在弯曲极限状态下的强度及有效宽比进行了分析。基于弹塑性应力－应变理论及箱梁剪滞效应的分析结果，本文推导出在有限塑性变形条件下，箱梁的极限强度增大系数及翼缘有效宽比与跨宽比及允许塑性变形值之间的关系及剪滞系数的计算方法。通过算例分析，为实际工程设计应用提供了有关计算方法、准则及可供参考的分析结论。

In this paper, for the thin walled linear strengthened steel box beam, the strength and valid width ratio of flange is investigated under the condition of elastoplastic limit state. Based on the elastoplastic stress strain theory and shear lag analysis results of thin walled box beam,the relationship of limit strength growing coefficient and flange valid width ratio of box beam versus span width ratio and allowed plastic deformation is established, and numerical analysis results are given. Thus, for the applications of this theory in the structure design, related calculation formulas and useful reference analysis results are suggested.