Seismic performance evaluation of existing light poles on elevated highway bridges
Seismic performance evaluation of existing light poles on elevated highway bridges
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DOI：
10.1080/15732479.2020.1760894
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发表时间：
2020-05
影响因子：
3.7
通讯作者：
D. Siringoringo;Y. Fujino;Ayami Nagasaki;Takuro Matsubara
中科院分区：
文献类型：
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作者：
D. Siringoringo;Y. Fujino;Ayami Nagasaki;Takuro Matsubara
摘要在过去的几次大地震中，我们观察到了安装在高架公路或铁路桥梁上的灯杆和电线杆的损伤。主要是由于杆杆过度变形、屈服引起的弯曲破坏、杆杆屈曲和桅杆坠落。这些破坏不仅影响了功能，而且阻碍了交通，使灾区的灾后恢复变得更加复杂。虽然在抗震规范中对高架公路桥梁的抗震性能进行了评价和升级，但大多数轻型电线杆和电线杆都是针对风荷载设计的，而不是针对地震设计的，因此对其抗震性能的评价很少。本文对高架桥上典型灯杆的抗震性能进行了研究。本研究包括既有灯杆的模态试验分析、有限元仿真和既有高架桥灯杆的实例分析。有限元模拟结果表明，当桥梁的固有频率与灯杆的基频接近时，会产生响应放大。由于固有的低结构阻尼，灯杆在共振时经历了很大的放大，当最大应力超过屈服应力极限时，导致弯曲破坏。
Abstract Damages on light poles and utility poles mounted on elevated highway or railway bridges were observed in the past several large earthquakes. They were mostly due to excessive pole deformation, bending failure caused by yielding, buckling of the pole and falling of the mast. The damages did not only affect functionalities but also impeded the traffic and further complicated post-earthquake recovery of affected area. While seismic resistance of elevated highway bridges has been evaluated and upgraded in the seismic codes, most light and utility poles were designed for wind loading and not for earthquake, so their seismic performances were rarely evaluated. In this research, seismic performance of a typical light pole mounted on elevated highway bridges is investigated. The study includes experimental modal analysis of existing light pole, finite element simulation, and case study of the light pole on existing elevated highway bridge. The results of finite element simulations show that response amplification occurs when the bridge’s natural frequency is within a close range of the light pole’s fundamental frequency. Due to inherently low structural damping, the light pole experiences large amplification at the resonance, and this leads to bending failure when the maximum stress exceeds the yield stress limit.