带端板螺栓连接可更换耗能梁段的高强钢框筒结构抗震性能试验研究

Experimental study on seismic performance of high-strength steel framed-tube structures with end-plate connected replaceable shear links

为了改善传统钢框筒结构抗震性能较差的问题,提出了带端板螺栓连接可更换剪切型耗能梁段的高强钢框筒结构(HSS-FTS-RSLs)。考虑耗能梁段长度和楼板的影响,设计了3个2/3比例的单层单跨HSS-FTS-RSLs子结构试件,对这3个试件进行低周往复加载试验并进行耗能梁段的更换,研究HSS-FTS-RSLs的抗震性能和震后可更换能力。试验结果表明:带端板螺栓连接的子结构试件在地震作用下滞回曲线饱满,损伤主要集中于耗能梁段,具有良好的抗震性能;更换耗能梁段后不会影响结构的刚度和承载力以及连接处的传力性能,结构的可更换允许残余层间侧移为0.40%;楼板可以使结构的弹性刚度和承载力分别提高7.40%和5.21%,楼板损伤主要集中在耗能梁段与裙梁连接区域上方;剪切型耗能梁段在循环荷载作用下超强系数为1.63~1.81,最大塑性转角可达到0.15~0.21rad,呈现出良好的超强和变形能力;耗能梁段长度比e/(Mp/Vp)(其中e为耗能梁段长度,Mp、Vp分别为耗能梁段的塑性受弯承载力和塑性受剪承载力)越小,结构的刚度和承载力越高,耗能梁段的变形能力越强。

High-strength steel framed-tube structures with end-plate connected replaceable shear links(HSS-FTS-RSLs) were proposed to improve the poor seismic performance of the traditional steel frame-tube structures. A series of cyclic loading tests were conducted to investigate the seismic performance and post-earthquake replaceability of HSS-FTS-RSLs, and replacing damaged shear links were also considered. Three 2/3-scale one-story one-bay sub-structure specimens were tested considering the effects of shear link length and reinforced concrete slab. The results show that the hysteretic curves for each specimen are plump, and inelastic deformation is concentrated on the shear links, presenting excellent seismic performance. The stiffness and bearing capacity of the specimens with the replaced shear links does not deteriorate, and the connections can continue to work well after replacing new shear links. The replaceability of shear links can be confirmed even in the presence of residual story drift of 0.40 %. The elastic stiffness and the bearing capacity can be increased by 7.40% and 5.21%, respectively, owing to the contribution of the slab. Slab suffers the most damage concentrated above the beam-to-link connections. The overstrength factors of the shear links vary from 1.63 to 1.81, and the maximum inelastic rotation ranges from 0.15 rad to 0.21 rad, exhibiting significant overstrength and great deformation capacity. The shear links with a small length ratio of e/(Mp/Vp)(e is the length of the shear links, Mp and Vp are the plastic flexural and plastic shear strength of the shear links, respectively) can obtain the great stiffness, bearing capacity and deformation capacity.