Aerodynamic damping properties of two transmission towers estimated by combining several identification methods

作者：Takeuchi Mayumi^*; Maeda Junji; Ishida Nobuyuki

来源：Journal of Wind Engineering and Industrial Aerodynamics, 2010, 98(12): 872-880.

DOI：10.1016/j.jweia.2010.09.001

• Aerodynamic damping
• 3D behaviors of a coupled tower-and-conductors system
• Normal decomposition method
• Multi-degree-of-freedom RD technique

Based on full-scale measurement data we report on several aerodynamic damping properties of two transmission towers under conditions of strong winds In estimating the damping ratio from data that contain many components of close frequencies of tower and conductor vibrations we cannot estimate the damping ratio of each component if we use an estimation method available for only a single-degree-of-freedom system Therefore, we combined several identification methods and are introducing a new method of estimating damping properties This method is applicable to the response record of a multi-degree-of-freedom system such as the coupled structure of a transmission tower-and-conductors Using the new estimation procedure we were able to extract the component of every vibration mode of the towers from a measured time history and estimate the accurate damping ratios individually, and our results revealed that the wind speed dependency of the aerodynamic damping property of the coupled tower-and-conductors system had wide differing characteristics depending on the vibration mode Moreover using a three-dimensional nonlinear analysis we discuss in detail the effects of the progressive deformati

• 出版日期2010-12