带铅阻尼器冷弯薄壁型钢组合墙抗震性能试验

Seismic performance of cold-formed thin-walled steel composite wall with lead damper

锁铆或自攻螺钉连接的冷弯薄壁型钢组合墙在低周往复加载试验中,滞回曲线“捏拢”现象较为严重、耗能能力较差.为减轻地震作用下冷弯薄壁型钢组合墙的破坏,提高结构体系的耗能能力,提出了一种带有铅阻尼器的冷弯薄壁型钢组合墙结构体系,并基于冷弯薄壁型钢组合墙的角部连接方式、面板铆钉间距及种类3种变量对其进行抗震性能试验研究.试验结果表明:加入铅阻尼器后,基于锁铆或自攻螺钉连接的冷弯薄壁型钢组合墙结构体系在低周往复荷载作用下,变形能力和耗能能力均有大幅度提升,刚度退化趋于平缓,损伤指数有较明显的降低,破坏形态也得到优化,但屈服荷载及峰值荷载略有降低;其次减小铆钉间距后,组合墙的屈服荷载、峰值荷载、峰值位移、抗剪强度得到一定程度的提高,但能量耗散系数差别不大;同时基于锁铆连接的冷弯薄壁型钢组合墙的屈服位移、屈服荷载、峰值位移、峰值荷载也明显高于基于自攻螺钉连接的冷弯薄壁型钢组合墙,延性及能量耗散系数相差不大.

In the low-cycle reciprocating loading test of cold-formed thin-walled steel composite wall connected with rivet locking or self-tapping screw,the phenomenon of“pinching”of hysteresis curve is serious and the energy dissipation capacity is poor.To reduce the damage of cold-formed thin-wall steel composite wall under earthquake and improve the energy dissipation capacity of the structure,a cold-formed thin-wall steel composite wall structure system with lead damper was proposed,and seismic performance experimental study was conducted based on three variables,i.e.,cold-formed thin-walled steel composite wall corner connection mode,panel rivet spacing,and type.Results show that with the addition of the lead damper,the deformation capacity and energy dissipation capacity of the cold-formed thin-walled steel composite wall structure system based on rivet locking or self-tapping screw connection were significantly improved under the low-cycle reciprocating loading.The stiffness degradation tended to be gentle,the injury index was significantly decreased,and the failure pattern was optimized,while the yield load and peak load were slightly reduced.Then,with the rivet spacing reduced,the yield load,peak load,peak displacement,and shear strength of the composite wall were improved to some extent,but the energy dissipation coefficient had little difference.Meanwhile,the yield displacement,yield load,peak displacement,and peak load of the cold-formed thin-walled steel composite wall based on rivet connection were significantly higher than those of the cold-formed thin-walled steel composite wall based on self-tapping screw connection,but the ductility and energy dissipation coefficient of the walls were similar.