WIT Press


A Wavelet-based Method To Simulate Gust Response Of Structures

Price

Free (open access)

Volume

84

Pages

10

Published

2005

Size

688 kb

Paper DOI

10.2495/FSI050461

Copyright

WIT Press

Author(s)

T. Kitagawa

Abstract

Under winds having stationary stochastic processes, the standard deviation of the gust response displacements of a structure is generally obtained with the frequency domain analysis, and the maximum response amplitude is estimated using the standard deviation and the peak factor. On the contrary, in the case of wind having time-dependent characteristics, the frequency domain analysis is not practical and it is impossible to estimate the maximum response amplitude. In order to overcome this underlying problem, a wavelet-based method to simulate the time history of the gust response is suggested in this study. The time-scale characteristics in wind fluctuations are configured with the system of the discrete wavelet, and their effects are reflected in the time histories of the gust responses to be synthesized. The horizontal gust responses of a structure in various wind velocity fluctuations are simulated with the proposed method, and the accuracy of the predicted response time history is discussed. Keywords: gust response, peak factor, structure, wavelet, wind fluctuation. 1 Introduction The aerodynamic forces on structures are generally expressed as the sum of the buffeting forces and the motion-induced forces. These forces include the frequency-dependent characteristics, and the frequency domain analysis [1, 2] has been conventionally used to estimate the gust responses of structures; many studies were performed on incorporating these frequency-dependent characteristics in this analysis. However, the frequency domain analysis is applicable only under the assumption of winds having stationary stochastic processes. The time domain analysis is then required in order to reflect the timedependent characteristics present in winds to the gust responses, in which case a

Keywords

gust response, peak factor, structure, wavelet, wind fluctuation