十字形截面钢异形柱的抗震性能和板件宽厚比限值研究

按照强震区多、高层钢框架结构柱的受力工况,以现行国标型钢组合的工程应用为目标,设计不同轴压比下不同翼缘宽厚比与不同腹板高厚比组合的36个十字形截面钢异形柱模型,模型截面应力相似系数为1,缩尺比为1∶2。考虑试件的初始缺陷和材料非线性,对这些模型系统地进行常轴力、低周反复荷载下的有限元计算。模拟模型的受力、变形、破坏全过程,研究变形模式、破坏模态、滞回性能、承载能力、耗能能力等抗震性能,并分析翼缘宽厚比、腹板高厚比和轴压比对抗震性能的影响规律,对模型的整体抗震性能进行综合评价。最后,基于抗震设计承载力取值和整体抗震性能的要求,提出不同轴压比下,能够在强震区使用的十字形截面钢异形柱翼缘宽厚比与腹板高厚比的组合限值,为工程应用和钢异形柱结构技术规程的编制提供理论依据。

RESEARCH ON ASEISMIC PERFORMANCE AND LIMIT VALUE OF PLATE WIDTH-THICKNESS RATIO OF STEEL SPECIALLY SHAPED COLUMNS WITH CRUCIFORM SECTION

Referencing to the load conditions of steel frame column members in meizoseismal area and aiming at engineering application of profiled bar combination under active international code, this paper designed a total of 36 calculation models of steel specially shaped columns with cruciform section of different flange width-thickness ratio and web depth-thickness ratio under different axial compression ratio, which were equal-stress and 1:2 scale. These models were analyzed by the numbers under low cyclic loading and constant axial compression considering their initial imperfection and material nonlinearity. The paper simulated the entire process of their forcing, deformation and destruction, studied their seismic performance such as bearing capacity, rotational performance, hysteretic behavior, energy dissipation capacity, destruction mode and so on, also analyzed the influencing rule of flange width-thickness ratio, web depth-thickness ratio and axial compression ratio on the seismic performance, and evaluated the holistic seismic behavior of these models. Finally, based on the requirements of seismatic bearing capacity and holistic seismic performance, the paper proposed the limit values of flange width-thickness ratio and web depth-thickness ratio under different axial compression ratio for application of steel specially shaped columns with cruciform section in meizoseismal area, and provided theoretical foundation for practical engineering applications and the compilations of Technical Specification for Steel Structures with Specially Shaped Columns.