Cyclic rotation capacity of beam-to-column connections using the various steel grade
Cyclic rotation capacity of beam-to-column connections using the various steel grade
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使用不同钢种的梁柱连接的循环旋转能力
DOI：
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
山田哲
中科院分区：
文献类型：
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作者：
Ryota Sato;佐藤亮太;S. Kishiki;吉敷祥一;S. Yamada;山田哲
在1995年的神户地震中，许多钢结构的梁柱连接处遭受损坏。在那些受损的建筑物中，观察到梁柱连接处的梁翼缘断裂。此后，针对防止梁柱连接早期断裂、提高钢梁的塑性变形能力进行了大量的研究。这些研究指出，日本抗弯框架RHS柱面板的面外变形导致梁腹板接头效率小，导致梁翼缘断裂限制了梁的塑性转动能力。在日本的高层建筑中，梁翼缘的现场全熔透焊接必须采用螺栓连接梁腹节点（WBFW型连接）来实现。然而，螺栓梁腹板接头存在接头效率差的问题。近年来，WBFW连接件在长时间、多次小幅变形地震动作用下的塑性变形能力已成为日本结构工程师非常重要的问题。 WBFW型连接的塑性变形能力通过以断裂寿命为纵轴、延展系数为横轴绘制的低周疲劳特性来评价。然而，很难对钢种、梁跨度等不同试验条件下的多项试验结果进行评估。本文进行了循环加载试验，重点提出了WBFW型连接塑性变形能力的合适评估方法。测试了三种类型的样本。每组样本具有相似的接头效率和连接细节。第一组试件采用400MPa常规强度钢，第二、第三组试件分别采用490MPa常规强度钢和590MPa高强度钢。试验结果可概括如下：(1)590MPa高强钢梁柱连接在1.5θp等转角加载14个循环后发生断裂，而400MPa常规强度钢梁柱连接表现出足够的塑性变形能力； (2)在基于最大旋转角度的低周疲劳特性评价中，590MPa高强钢的塑性变形能力与其他材料基本相同； （3）最后，在不同的试验条件（如钢种和梁跨度）下评估多次试验结果是非常有效的。
In the 1995 Kobe earthquake, many steel structures suffered damage at beam-to-column connections. And in those damaged buildings, fractures of a beam flange at the beam-to-column connections were observed. After that, a remarkable number of studies have been conducted to prevent early fracture at beam-to-column connections and enhance the plastic deformation capacity of steel beams. In these researches, it was pointed out that the small joint efficiency of the beam web, which is caused by the out-of-plane deformation of the skin plate of RHS column used for moment resisting frames in Japan, decreases plastic rotation capacity of the beam limited by the fracture of the beam flange. In the high-rise buildings of Japan, the on-site full penetration welding to beam flanges has to be achieved with the bolted beam-web joint (WBFW type connection). However, the bolted beam-web joint has problem of the poor joint efficiency. Recently, the plastic deformation capacity of the WBFW connections subjected to a long-duration earthquake of ground motion with many cycle of small amplitude of deformation has become a very important issue for structural engineers in Japan. The plastic deformation capacity of the WBFW type connections is evaluated by low cycle fatigue characteristics plotted with fracture life as the vertical axis and ductility factor as the horizontal axis. However, it is difficult to evaluate several test results with various test conditions such as steel grade and beam span. In this paper, cyclic loading tests focusing on suggesting an appropriate evaluation method of plastic deformation capacity of WBFW type connections were carried out. Three types of specimen were tested. Each group of specimens has similar joint efficiency and connection details. The 400MPa conventional strength steel was used for the first group of specimen, and the 490MPa conventional strength steel and the 590MPa high strength steel was used for the second and third ones, respectively. The test results can be summarized as follows:(1) the beam-to-column connection made of the 590MPa high strength steel fractured in 14 cycles of constant rotation angle loading of the 1.5θp, although that of the 400MPa conventional strength steel showed sufficient plastic deformation capacity; (2) the plastic deformation capacity of the 590MPa high strength steel is almost the same as that of the others in evaluation of low cycle fatigue characteristics based on the maximum rotation angle; (3) finally, it was very effective to evaluate several test results with various test condition such as steel grade and beam span.