Release Time:2019-03-11  Hits:

Indexed by: Journal Article

Date of Publication: 2018-05-01

Journal: JOURNAL OF AEROSPACE ENGINEERING

Included Journals: EI、SCIE

Volume: 31

Issue: 3

ISSN: 0893-1321

Key Words: Frequency identification; Higher-order spectrum; Power spectrum; Practical bridge

Abstract: Identifying the frequencies of practical bridges can help in understanding the bridge dynamic property. However, the vibration amplitude excited by wind load and traffic load is too small, resulting in a small signal noise ratio, which affects the performance of frequency identification. This paper proposes frequency identification procedures for practical bridges to reduce the influence of noise through higher-order spectrum. First, a higher-order spectrum is introduced. Then, the frequency identification procedures are presented for practical bridges. Finally, the proposed procedures are applied to a practical bridge. A higher-order spectrum can eliminate the influence of Gaussian white noise (GWN) or reduce nonstationary random noise during frequency identification. The advantage of using the higher-order spectrum to identify frequencies is verified by simple artificial signals combined with sinusoidal signals with different frequencies and GWN. The results show that the second-order spectrum obtained by the higher-order spectrum has better frequency identification performance than the tradition spectrum and that the frequencies of the practical bridge can be identified successfully. (c) 2018 American Society of Civil Engineers.