薄柔构件屈曲铰弯矩转角曲线分析

Investigation on Moment-Rotation Curves of Local Buckling Hinges of Slender Members

本文对薄柔构件的局部屈曲段的弯矩转角性能进行了研究。基于屈曲段的受力变形特征,引入了屈曲铰的概念来类比于厚实截面中的塑性铰。对超过500个构件屈曲铰的弯矩转角曲线进行了分析。根据曲线形状并结合截面翼缘宽厚比、腹板高厚比及构件轴压比三大参数对弯矩转角曲线进行分类;归纳出了每一类曲线对应的截面参数范围。且根据这些参数对每一类的曲线进行公式拟合。本文分析为薄柔构件钢框架的整体结构推覆分析提供了参考。

The moment-rotation capacity was investigated for slender elements. Based on the deformation character in the local buckling segment, the local buckling hinge similar to the plastic hinge that often occurs in compact elements, was proposed in this paper. The moment-rotation curves of more than 500 elements were investigated. Those curves were classified into different categories as per three factors： the width-to-thickness ratio of flange, the depth-to-thickness ratio of web and the axial force ratio of the member. For each category of curves, the scopes of the ratios were then defined and the fomula were derived by using these factors. The results in this paper can give references to the push-over method for the steel frames composed of slender ele- ments.