局部约束轧制H型钢柱的抗震性能研究

Experimental study of confined hot-rolled H-shape steel columns under cyclic loading

针对地震作用下钢抗弯框架由于H型钢柱局部屈曲所产生的破坏,提出了一种适用于地震区的钢框架结构形式:局部约束的轧制H型钢柱体系。这种结构形式通过在柱可能产生局部屈曲的部位设置附加约束,以达到延缓屈曲发展,提高柱抗震性能的目的。根据所提出的方法,通过两组共7根大比例模型柱进行了常轴力和水平循环荷载作用下的试验验证。研究结果表明,未约束H型钢模型柱在达到其最大承载力之后,由于柱底部局部屈曲不断发展,承载力下降较快;而所建议的局部约束H型钢柱,其延性及抗震耗能能力都有了较大提高。

Local buckling of H-shape steel columns caused by cyclic loading often brings damage to moment-resisting frames. In order to solve this problem, an innovative confinement has been proposed, aiming at preventing or delaying the inelastic buckling of H-shape steel columns at the potential plastic hinge zones. Seven large-scale model columns were tested under constant axial load and cyclic lateral forces. The test results validated the concept of confined H-shape steel columns. Moreover, compared with the conventional model columns, the confined model columns exhibited improved seismic performance with large ductility.