冷弯薄壁型钢框架-开缝钢板剪力墙力学性能研究

STUDY ON THE MECHANICAL PROPERTIES OF COLD-FORMED STEEL FRAMED SHEAR WALL WITH SLITS

为研究适用于低层和多层冷弯薄壁型钢建筑的冷弯薄壁型钢框架-开缝钢板剪力墙(Cold-formed steel Framed Shear Wall with Slits,简称CFS-WS),该文开展了1面普通CFS-WS和3面加劲CFS-WS的拟静力试验,得到了CFS-WS的破坏形态、滞回曲线、骨架曲线和耗能能力等力学性能,提出了其抗剪承载力设计值。试验结果表明:CFS-WS加载时依靠竖缝间钢板“扭转-恢复-逆向扭转”和型钢框架变形来共同抵抗水平荷载和耗散能量,试件破坏时钢板撕裂,帽形柱端部屈曲;CFS-WS具有良好的承载力、塑性、延性和耗能能力,但其滞回曲线捏缩现象较为严重;加劲CFS-WS较普通CFS-WS而言,其抗剪刚度、承载能力和耗能能力更高,滞回曲线捏缩现象有所减轻。此外,通过加劲肋连接件将加劲肋和冷弯薄壁型钢梁柱连接成钢框架,可有效提高CFS-WS的前期抗剪刚度、承载力和耗能能力,大大改善结构的抗震性能。

In order to study the mechanical behavior of the cold-formed steel framed shear wall with slits(CFSWS)which is suitable for low-rise and multi-story cold-formed thin-walled steel buildings,pseudo-static tests of 1 ordinary CFS-WS and 3 buckling-restrained CFS-WS were conducted to gain the mechanical properties of CFSWS,including the failure modes,load-displacement hysteresis curves,skeleton curves and energy dissipation capacities,and the design value of shear capacity was put forward.The test results indicates that the CFS-WS relies on the"torsion-recovery-reverse torsion"of steel plate between vertical slits and the deformation of the steel frame to resist horizontal loads and dissipate energy.The steel plate tears and the end of the hat column buckles when the CFS-WS is broken.The CFS-WS has good bearing capacity,plasticity,ductility and energy dissipation capacity;however,the rheostriction of its load-displacement hysteresis curve is rather severe.Compared with ordinary CFS-WS,the buckling-restrained CFS-WS has higher shear stiffness,bearing capacity and energy dissipation capacity,and the rheostriction of its load-displacement hysteresis curve is mitigated.Furthermore,the stiffeners and the cold-formed steel beams and columns are connected to form a steel frame through the stiffener connectors,which can effectively enhance the early shear stiffness,bearing capacity and energy dissipation capacity of CFS-WS,and greatly improve the seismic performance of the structure.