H形截面钢构件绕弱轴抗弯承载力

Moment Resistance of H section Steel Members Bent About Minor Axis

摘要:

对H形截面钢构件绕弱轴弯曲的性能进行研究，考虑了抗弯承载力与板件宽厚比之间的关系.基于经实验校准的非线性有限元模型，模拟了不同翼缘和腹板宽厚比组配的H形截面钢构件绕弱轴弯曲的全过程，并对破坏模式进行了机理分析.研究发现，对于工程中常用的H形截面钢构件，极限前性能主要由翼缘宽厚比决定；极限后翼缘和腹板之间存在显著的相关作用.最后，给出了绕弱轴弯曲时可达到塑性抗弯能力的H形截面钢构件宽厚比上限值，并提出了有效塑性宽度计算法计算H形截面钢构件绕弱轴弯曲的极限抗弯承载力.

Abstract:

The behavior of H section steel members bent about the minor axis was thoroughly investigated by taking the relationship of the plate element slendernesses with the flexural resistance into consideration. A finite element analysis was conducted to investigate the whole loading process behavior of H section steel members composed of different combinations of flange and web slendernesses bent about their minor axis, where the failure mechanism was derived from the stress development curves. It is found that the behavior of such members in pre ultimate stage is mainly affected by the flange width to thickness ratio; while the behavior of such members in the post ultimate stage is significantly affected by the flange web interaction. In addition, the proposed slenderness limit for H section members was put forward, which could attain their full plastic moment resistance when they being bent about the minor axis. Finally, the effective plastic width method for calculating ultimate strength was put forward.