Identification of modal parameters of long-span bridges under various wind velocities
Abstract The modal parameters identification of bridges under non-stationary environmental excitation has caught the attention of researchers. This paper studies the non-stationarity of wind velocity, and extracts the time-varying mean wind velocity based on a discrete wavelet transform and recursiv...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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SpringerOpen
2022-12-01
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| Series: | Advances in Bridge Engineering |
| Subjects: | |
| Online Access: | https://doi.org/10.1186/s43251-022-00071-0 |
| _version_ | 1828264719443558400 |
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| author | Siying Lu Lei Yan Xuhui He Hui Guo |
| author_facet | Siying Lu Lei Yan Xuhui He Hui Guo |
| author_sort | Siying Lu |
| collection | DOAJ |
| description | Abstract The modal parameters identification of bridges under non-stationary environmental excitation has caught the attention of researchers. This paper studies the non-stationarity of wind velocity, and extracts the time-varying mean wind velocity based on a discrete wavelet transform and recursive quantitative analysis. The calculated turbulence intensity and turbulence integral scale under the non-stationary model are smaller than those under the stationary model, especially the turbulence integral scale. The empirical wavelet transform is used to identify the modal parameters of long-span bridges, and the power spectral density spectrum is proposed as a replacement for the Fourier spectrum as the basis of the frequency band selection. The bridge modal parameters are then compared using the covariance-driven stochastic subspace system identification method (SSI-COV) and the Hilbert transform method based on an improved empirical wavelet transform (EWT-HT). Both methods can accurately identify the modal frequency, and the absolute difference between these two methods is equal to 0.003 Hz. The wind velocity results in a change of less than 1% in the modal frequency. The absolute difference between the modal damping ratios identified using SSI-COV and EWT-HT is significant and can reach 0.587%. The modal damping ratios are positively correlated with the mean wind velocities, which aligns with the quasi-steady assumption. In addition, the applicability of SSI-COV and EWT-HT is also evaluated using the standard deviation, coefficient of variation, and range dispersion indicators. The results show that the EWT-HT is more applicable to the identification of the modal parameters of long-span bridges under non-stationary wind velocities. |
| first_indexed | 2024-04-13T04:28:58Z |
| format | Article |
| id | doaj.art-cc1e748435d14407bde9e0a440af39fd |
| institution | Directory Open Access Journal |
| issn | 2662-5407 |
| language | English |
| last_indexed | 2024-04-13T04:28:58Z |
| publishDate | 2022-12-01 |
| publisher | SpringerOpen |
| record_format | Article |
| series | Advances in Bridge Engineering |
| spelling | doaj.art-cc1e748435d14407bde9e0a440af39fd2022-12-22T03:02:23ZengSpringerOpenAdvances in Bridge Engineering2662-54072022-12-013112110.1186/s43251-022-00071-0Identification of modal parameters of long-span bridges under various wind velocitiesSiying Lu0Lei Yan1Xuhui He2Hui Guo3School of Civil Engineering, Central South UniversitySchool of Civil Engineering, Central South UniversitySchool of Civil Engineering, Central South UniversityRailway Engineering Research Institute, China Academy of Railway SciencesAbstract The modal parameters identification of bridges under non-stationary environmental excitation has caught the attention of researchers. This paper studies the non-stationarity of wind velocity, and extracts the time-varying mean wind velocity based on a discrete wavelet transform and recursive quantitative analysis. The calculated turbulence intensity and turbulence integral scale under the non-stationary model are smaller than those under the stationary model, especially the turbulence integral scale. The empirical wavelet transform is used to identify the modal parameters of long-span bridges, and the power spectral density spectrum is proposed as a replacement for the Fourier spectrum as the basis of the frequency band selection. The bridge modal parameters are then compared using the covariance-driven stochastic subspace system identification method (SSI-COV) and the Hilbert transform method based on an improved empirical wavelet transform (EWT-HT). Both methods can accurately identify the modal frequency, and the absolute difference between these two methods is equal to 0.003 Hz. The wind velocity results in a change of less than 1% in the modal frequency. The absolute difference between the modal damping ratios identified using SSI-COV and EWT-HT is significant and can reach 0.587%. The modal damping ratios are positively correlated with the mean wind velocities, which aligns with the quasi-steady assumption. In addition, the applicability of SSI-COV and EWT-HT is also evaluated using the standard deviation, coefficient of variation, and range dispersion indicators. The results show that the EWT-HT is more applicable to the identification of the modal parameters of long-span bridges under non-stationary wind velocities.https://doi.org/10.1186/s43251-022-00071-0Non-stationary wind velocityFull-scale measurementsModal identificationEmpirical wavelet transformStructural health monitoringTheoretical aerodynamic damping |
| spellingShingle | Siying Lu Lei Yan Xuhui He Hui Guo Identification of modal parameters of long-span bridges under various wind velocities Advances in Bridge Engineering Non-stationary wind velocity Full-scale measurements Modal identification Empirical wavelet transform Structural health monitoring Theoretical aerodynamic damping |
| title | Identification of modal parameters of long-span bridges under various wind velocities |
| title_full | Identification of modal parameters of long-span bridges under various wind velocities |
| title_fullStr | Identification of modal parameters of long-span bridges under various wind velocities |
| title_full_unstemmed | Identification of modal parameters of long-span bridges under various wind velocities |
| title_short | Identification of modal parameters of long-span bridges under various wind velocities |
| title_sort | identification of modal parameters of long span bridges under various wind velocities |
| topic | Non-stationary wind velocity Full-scale measurements Modal identification Empirical wavelet transform Structural health monitoring Theoretical aerodynamic damping |
| url | https://doi.org/10.1186/s43251-022-00071-0 |
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