Numerical and experimental study of vibration mitigation for highway light poles

Highway light poles are slender structures usually characterized by low values of structural damping, a factor that can lead to large-amplitude vibration sometimes leading to collapse. This paper is motivated by a recent investigation, conducted to identify the reason for repeated failures, experienced by aluminum tapered light poles in the State of Illinois during a winter storm. The study combined numerical and experimental full-scale analysis of the structural system and its response to simulated external actions. It was observed that, despite the simple structural form, the definitive identification of the mechanism causing the oscillations was challenging due to inherent variability in the configuration as well as the paucity of environmental and response data. However, a plausible mechanism was identified, and a mitigation technique was proposed and evaluated for amplitude reduction.