装配式耗能减震节点连接中削弱型约束钢板阻尼器滞回性能试验

Tests for hysteretic performance of weakened constrained steel-plate damper in prefabricated energy dissipation joints

为解决装配式框架节点与连接的抗震能力不足、震损后难修复等问题,提出一种新型装配式耗能减震节点连接,对其关键耗能减震部件-可更换削弱型约束钢板阻尼器进行低周往复加载试验,考察其承载能力、耗能能力、刚度退化与延性等滞回性能,揭示阻尼器的失效破坏机制,分析开孔削弱形式、削弱长度、钢板厚度以及约束套筒与削弱钢板的间隙等对阻尼器力学性能的影响。结果表明:可更换削弱型约束钢板阻尼器在削弱截面部位开裂或断裂,实现了阻尼器的塑性耗能与失效模式可控,具备良好的承载-耗能双重功能。在相同参数条件下狗骨削弱型约束钢板阻尼器的承载能力、耗能能力与延性性能优于竖缝开孔削弱型约束钢板阻尼器。削弱长度对延性与钢板侧向屈曲性能影响较大,钢板厚度对承载能力与刚度退化性能影响较大,而约束套筒与钢板间隙较大时,约束套筒不能有效发挥作用,易导致削弱钢板发生受压屈曲。

Here,in order to solve problems of insufficient aseismic capacity and difficult to repair after earthquake damage of prefabricated frame joints and connections,a new type of prefabricated energy dissipation joint connection was proposed.Low-cycle repeated loading tests were conducted for its key energy dissipation component called the replaceable weakened restrained steel-plate damper to investigate its hysteretic performances of load-bearing capacity,energy dissipation capacity,stiffness degradation and ductility,reveal its failure mechanism,and analyze effects of slot-opened weakening form,weakening length,steel plate thickness and gap between restraint sleeve and weakened steel plate on mechanical properties of the damper.The results showed that the replaceable weakened restrained steel plate damper cracks or breaks at the position of weakened section to realize controllable plastic energy dissipation and damper failure mode,and have good dual-function of load-bearing and energy dissipation;under the same parameters,load-bearing capacity,energy dissipation capacity and ductility of dog bone weakened restrained steel plate damper are better than those of vertical slot-opened weakened restrained steel plate damper;weakening length has a larger effect on ductility and lateral buckling performance of steel plate,steel plate thickness has a larger effect on load-bearing capacity and stiffness degradation performance;when gap between restraint sleeve and steel plate is larger,restraint sleeve can’t have effective action to cause the compression buckling of weakened steel plate.