A Framework for Vibration Attenuation in Traffic Mast Arm Structures under Wind Loads

Abstract

Traffic signals and information signs play a vivid role in maintaining safe travel by guiding drivers on highways and urban roads. Traffic mast arm structures are susceptible to vibrations induced by wind loads. Fatigue-induced failure is common in these structures. However, it is crucial to ascertain the functionality of signal support structures. This paper lays the foundation for a fully computational framework to model and mitigate wind-induced vibrations in traffic lighting support structures by conducting computational fluid dynamics (CFD) simulations, dynamic modeling, and damping enhancement. We validated the CFD simulations by aerodynamic testing. The dependence of flow pattern and aerodynamic loads on Reynolds number reveals the importance of full-scale CFD with large eddy simulation for wind load estimation on mast arm structures. Distributed tuned mass dampers were created by employing available weights of lighting boxes. The results show that distributed tuned lighting boxes are effective for vibration suppression. Besides, damping enhancement can significantly reduce vibration-induced stresses and hence extend the fatigue life. The proposed mitigation technique promises to save construction costs and improve the safety of the traveling public. The procedure followed for creating time histories of wind loads integrated with finite element modeling applies to other vibration lessening techniques for potential inclusion in the AASHTO standard.

Aeroelastic metastructure for simultaneously suppressing wind-induced vibration and energy harvesting under wind flows and base excitations

“…Wind-induced vibrations can cause serious damage to buildings, bridges, and offshore structures. There are many scenarios that require protection from wind-induced vibration, such as bridge collapses [1,2], skyscraper wind-resistance design [3,4], arm masts of traffic lights [5,6] and road signs [7,8], cranes [9,10], aerofoils [11,12], and more. Traditional solutions for passive vibration suppression primarily involve the use of tuned mass dampers [13,14], nonlinear energy sink [15,16], etc.…”

Modeling of wind-induced vibration control and energy harvesting of traffic signal structures

“…Traffic signals are typically supported by cantilever structures consisting of a vertical pole (strain pole) and a horizontal mast arm (mast arm pole). These structures are particularly susceptible to wind-induced vibrations [1]. The low natural frequency resulting from the high flexibility, typically in the range of 0.7-1.4 Hz [2], overlaps with the excitation frequency of wind, which leads to large-amplitude resonant vibrations.…”