腋板加强型节点钢框架弹塑性动力时程分析

Elastic and plastic dynamic time-history analysis of steel frame with haunch-reinforced nodes

为研究腋板加强型节点钢框架在地震荷载作用下抗震性能,分别建立1∶2缩尺比例的腋板加强型节点空间钢框架(SHF)与普通节点空间钢框架(NSF)的ANSYS模型,通过加载罕遇地震波,分析两种节点类型框架在地震荷载作用下层间位移、最大层间位移角、反应加速度和柱底剪力.研究结果表明:腋板加强型节点框架具有明显的梁铰破坏机制,能显著地将梁端塑性铰外移到远离梁柱节点焊缝部位的梁上;腋板加强型节点框架最大层间位移角均小于普通节点框架,在一定程度上限制结构水平位移,避免结构出现较大变形;腋板加强型节点可以减少框架柱底剪力,结构在强震作用下柱脚剪切破坏程度有所降低.

In order to study seismic performance of steel frame with haunch-reinforced nodes under seismic load,1 ： 2 scale ratio ANSYS models of haunch-reinforced nodes space steel frame （SHF） and ordinary nodes space steel frame model （NSF） are established, with story drift, maximum ratio of story drift, response acceleration and column bottom shear force an-alyzed by loading rare seismic waves. The study shows th a t： SHF has obvious beam hinge failure mechanism which can transfer beam-end plastic hinge away from the welded connec-tions area of beam-column significantly; the maximum story-drift ratios of SHF are always smaller than the NSFs as can help to limit the structural horizontal displacement to some extent and avoid large deformation; SHF can reduce column bottom shear force and damage degree of shear failure on column bottom under seismic loads.