Cables of suspension, cable-stayed and tied-arch bridges, suspended roofs, and power transmission lines are prone to moderate to large-amplitude vibrations in wind because of their low inherent damping. Structural or fatigue failure of a cable, due to these vibrations, pose a significant threat to the safety and serviceability of these structures. Over the past few decades, many studies have investigated the mechanisms that cause different types of flow-induced vibrations in cables such as rain-wind induced vibration (RWIV), vortex-induced vibration (VIV), iced cable galloping, wake galloping, and dry-cable galloping that have resulted in an improved understanding of the cause of these vibrations. In this study, the parameters governing the turbulence-induced (buffeting) and motion-induced wind loads (self-excited) for inclined and yawed dry cables have been identified. These parameters facilitate the prediction of their response in turbulent wind and estimate the incipient condition for onset of dry-cable galloping. Wind tunnel experiments were performed to measure the parameters governing the aerodynamic and aeroelastic forces on a yawed dry cable. This study mainly focuses on the prediction of critical reduced velocity 〖(RV〗_cr) as a function of equivalent yaw angle (*) and Scruton number (Sc) through measurement of aerodynamic- damping and stiffness. Wind tunnel tests usingmore »
Wind-induced Response Characteristics of a Yawed and Inclined Cable in ABL Wind
Inclined cables used in bridges or other infrastructures are vulnerable to unsteady wind-induced loads producing moderate- to large-amplitude vibration that may result in damage or failure of the cables, resulting in catastrophic failure of the structure they secure. In the present study, wind-induced response of an inclined smooth cable was studied through wind tunnel measurements using a flexible cable model for a better understanding of the vibration characteristics of structural cables in atmospheric boundary layer wind. For this purpose, in-plane and out-of-plane responses of a sagged and a non-sagged flexible cable were recorded by four accelerometers. Four cases with different yaw and inclination angles of a cable with approximate sag ratios of 1/10 were studied to investigate the wind directionality effect on its excitation mode(s) and response amplitude. Cable tension was also measured during all experiments to assess the correlation of wind speed, excitation vibration mode, and natural frequency of the cable with change in cable tension. Additionally, two inclined cables with no sag were tested to determine the influence of sag of a cable on its vibration characteristics. In the second part of this study, a series of finite element analyses were conducted to predict the wind-induced aerodynamic damping more »
- Award ID(s):
- 1537917
- Publication Date:
- NSF-PAR ID:
- 10203854
- Journal Name:
- Engineering structures
- Volume:
- 214
- ISSN:
- 1873-7323
- Sponsoring Org:
- National Science Foundation
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