装配式损伤可控钢质铰滞回性能研究

Hysteretic Performance of Fabricated Damage-controllable Steel Hinges

为提高装配式梁柱节点的滞回性能,实现其损伤破坏区域的可控制性,提出一种装配式损伤可控钢质铰,钢质铰中设置狗骨式上下翼缘,使塑性铰外移远离节点核心区。设计两种不同构造形式的装配式损伤可控钢质铰,通过低周往复荷载试验与有限元参数分析,考察损伤可控钢质铰的滞回性能与损伤可控性能。结果表明,损伤可控钢质铰的塑性累积耗能发生在翼缘狗骨削弱区域,翼缘非削弱区域未屈服;损伤可控钢质铰的滞回曲线较为饱满,具有稳定的滞回性能和良好的耗能能力,两种钢质铰的延性系数都在7.0以上,等效黏滞阻尼系数都达到0.5以上,且强度无明显的退化;D字型钢质铰的滞回性能优于T字形钢质铰。L/b_(f)、b/L和c/b_(f)的变化对翼缘狗骨削弱型钢质铰的初始刚度影响较小,峰值承载力随着L/b_(f)、b/L和c/b_(f)的增大而减小,且c/b_(f)对峰值荷载的影响较为明显。

A fabricated damage-controllable steel hinge is proposed to improve the hysteresis performance of fabricated beam-to-column joints and achieve controllability of the damaged region,the flanges of the fabricated damage-controllable steel hinge are bog-bone weakened to concentrate the plastic damage in the reduced section and achieve the outward movement of the plastic hinge away from core joint.Two damage-controllable steel hinges with different configuration were designed,and the hysteretic performance as well as the damage controllability was investigated through low-cycle reciprocating load tests and finite element parametric analysis.The results showed that the plastic accumulative energy dissipation of the proposed steel hinge concentrated in the dog-bone weakened area,while no yield was found in the non-weakened area of the flange.The hysteretic curve for the proposed steel hinge was plumped,with stable hysteresis behavior and good energy dissipation capacity.The ductility coefficient of the two steel hinges was more than 7.0,and the equivalent viscous damping coefficient is above 0.5,while no obvious strength degradation was found.The hysteretic performance of specimen D was better than that of specimen T,since the plastic behavior developed in the web segment of specimen D,leading to improvement of the flexural bearing capacity,stiffness degradation capacity and energy dissipation capacity.The change of L/b_(f)、b/L and c/b_(f) rarely affected the initial stiffness,while the bearing capacity decreased with the increase of L/b_(f)、b/L and c/b_(f).