新型弧形钢棒阻尼器性能的有限元数值分析

Analysis on Performance of New Arc-Shaped Steel Damper by Finite Element Method

设计了一种新型弧形钢棒阻尼器,该阻尼器采用局部削弱构造,从而有效地解决了端部应力过大的问题。新型弧形钢棒阻尼器有两种削弱方案:A方案,端部截面尺寸不变,中部削弱;B方案,端部削弱,中部保持削弱后的截面尺寸不变。采用ABAQUS软件对其进行有限元分析,研究不同削弱方案对新型弧形钢棒阻尼器的滞回耗能能力、承载力特性、应力分布情况的影响。结果表明:两种方案的新型弧形钢棒阻尼器的等效粘滞阻尼系数均比弧形钢棒阻尼器大,耗能效果得到了提升,且A方案的新型弧形钢棒阻尼器耗能效果提升更多;随着削弱程度的增加各试件的滞回曲线逐渐收缩、等效粘滞阻尼系数呈先上升后下降的趋势、耗能量和初始刚度逐渐减小、峰值应力逐渐从耗能元件的两端转移至中部;采用A方案进行局部削弱时,中部截面直径宜控制在端部截面直径的70%～80%;采用B方案进行局部削弱时,中部截面直径宜控制在端部截面直径的60%～70%。

A new arc-shaped steel damper （ASSD） is proposed. The phenomenon of stress concentration in ends will not appear. Reduced scheme A （Ends part won＇t reduced, but middle part reduced） and B （End part reduces, middle part keeps the size of the reduced end part） are designed to study the hysteretic perform- ance, the loading capacity and the stress distribution. Numerical simulations with ABAQUS are conducted for all models. The analysis shows that the equivalent damper ratio of new ASSD is greater than that of ASSD. New ASSD has excellent energy dissipation capacity. Scheme A is better than scheme B. With the increasing of reduced degree, the hysteretic curve contracts gradually. The equivalent damper ratio increases first and then decreases. The initial stiffness and energy dissipation capacity decrease gradually. The peak stress of damper from middle part transfers to end part. Using scheme A for reduced, diameter of the section of middle part （b） should be controlled at 70% -80% of diameter of the section between connection plate and end part （d）. Using scheme B for reduced, b should be controlled at 60% -70% of d.