肋板補強鋼骨箱型柱梁柱接頭之耐震行為

Abstract

台灣的鋼骨結構系統以箱型柱與H型梁最為常見。以往之研究顯示傳統式接頭在反覆載重試驗下，試體在梁翼全滲透銲接處、扇形開孔處或梁翼兩側邊緣發生突然性之破壞。本研究以有系統之方法，包含有限元素分析與實尺寸梁柱接頭試驗，探討肋板補強式梁柱接頭之耐震行為。此外，更進一步探討背墊板對於肋板補強式梁柱接頭之影響程度。 本研究採垂直肋板補強之方式，以肋板銲接於柱翼板與鋼梁上下翼板。進行三組箱型柱實尺寸梁柱接頭反覆載重試驗。試驗結果顯示，肋板補強式接頭可有效降低箱型柱梁柱接頭全滲透銲接處與扇形開孔之應力，然而有微小裂縫於梁翼全滲透銲兩端形成。載重位移遲滯迴圈顯示試體具有良好之韌性能力。

Box columns and H beams are widely used in the steel frame buildings in Taiwan. The unexpected failure occurred in those conventional connections, described in the literature, initiated from the complete joint penetration (CJP) weld, weld access hole, and at the tips of the beam flange. This study is focused on investigating analytically and experimentally the behavior of the H beam to box column connections strengthened with vertical rib plates. An experiment was carried out to study the behavior of three full scale H beam to box column connections. The connections were reinforced with lengthened rib plate to the box column flange and the beam flange along the centerline of the beam flanges. Test results showed that the reinforced rib plate can reduce the stress concentration occurred at CJP weld and weld access hole. However, minor cracks were inspected in CJP weld at the tips of beam flanges. The connections strengthened with rib plate can develop excellent ultimate strength and moment-plastic rotation behavior.