大宽厚比开缝组合钢板墙低周反复荷载试验研究

Cyclic test on large flakiness ratio composite steel plate walls with slits

针对已有研究中开缝组合钢板墙开缝数量较多,使得墙板的抗侧刚度和承载力大大削弱的现象,对大宽厚比开缝组合钢板墙进行了试验研究。改进措施为采用预制混凝土板增加钢板的角部面外约束以防止墙板的整体屈曲。通过5个试件的反复荷载试验,研究大宽厚比开缝组合钢板墙的破坏模式、屈服承载力、极限承载力、延性、滞回性能以及耗能性能。试验结果表明,预制混凝土板角部设置约束装置可以有效避免试件的整体失稳,并改善大宽厚比开缝钢板墙的滞回性能。对大宽厚比开缝组合钢板墙试件进行的单调荷载和反复荷载作用下的有限元分析结果表明,单调荷载作用下的有限元分析结果明显低估试件的极限承载力,循环荷载作用下的骨架曲线与试验结果吻合较好,大宽厚比开缝组合钢板墙有明显的应变循环强化效应。相应地对大宽厚比开缝组合钢板墙极限承载力公式进行了改进。

Noting that lateral stiffness and strength of composite steel plate shear walls with slits were largely reduced due to large number of slits in previous study, test was performed on large width-to-thickness ratio composite steel plate shear walls with slits. Improvement by using out-of-plane restrainer for pre-cast concrete panel was proposed to prevent overall buckling of the composite wall. Five specimens were tested to investigate failure mode, bearing capacity, ductility, hysteretic behavior, as well as energy dissipation. The test shows that the additional restrainer can effectively prevent overall buckling of the specimens and greatly improve the hysteretic behavior of large width-to-thickness ratio composite walls with silts. Finite element analysis was performed on the specimens under monotonic loading and cyclic loading. The analytical results show that ultimate strength of the specimens under monotonic loading is underestimated significantly while skeleton curves of cyclic loading correlate well with test results. It is indicated that there is significant strain cyclic hardening effect in composite steel plate walls with slits. Formula of ultimate strength was accordingly improved.