Extremely Low-Cycle Fatigue Tests of Thick-Walled Steel Bridge Piers
Extremely Low-Cycle Fatigue Tests of Thick-Walled Steel Bridge Piers
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DOI：
10.1061/(asce)be.1943-5592.0000429
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发表时间：
2013-09
影响因子：
3.6
通讯作者：
H. Ge;L. Kang;Tsumura Yasuhiro
中科院分区：
文献类型：
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作者：
H. Ge;L. Kang;Tsumura Yasuhiro
为研究钢桥梁结构的极低周疲劳性能，对9个无加劲厚壁箱形截面钢桥墩进行了试验研究。各种参数的影响，包括横截面形状（有或没有一个扩展部分），加载模式，和宽厚比和细长比进行了研究。试验结果表明，延性裂纹发生在所有标本的柱脚无论循环加载的历史和延性裂纹的萌生寿命是敏感的加载模式，截面形状，和宽厚比。在所有试验中，延性裂纹开始于桥墩-底座焊缝，随后的循环载荷导致延性裂纹沿着腹板和翼缘方向在焊趾处扩展，然后扩展到母材，这引发了强度能力的明显下降。观察到延性裂纹萌生和最大强度之间存在显著延迟。此外，韧性裂纹的萌生和扩展可能伴随着局部屈曲。
To study extremely low-cycle fatigue performance of steel bridge structures, a total of nine steel bridge piers with unstiffened thick-walled box sections were tested in this study. The effects of various parameters, including cross-sectional shape (with or without an extension part), loading pattern, and width-thickness and slenderness ratios were investigated. Experimental results demonstrate that ductile cracks occurred at the column base in all specimens regardless of cyclic-loading histories and that ductile crack initiation life is sensitive to loading pattern, cross-sectional shape, and the width-thickness ratio. In all tests, the ductile crack began in the pier-to-base weld, and subsequent cyclic loads resulted in the ductile cracks growing at the weld toes along web and flange directions and then propagating into the base metal, which triggered an obvious decrease in strength capacity. A significant delay was observed between ductile crack initiation and maximum strength capacity. Moreover, ductile crack initiation and propagation may be accompanied by local buckling.