Data Fusion for System Identification of the Humber Bridge
In Operational Modal Analysis (OMA) of large structures, ambient vibration data from multiple non-simultaneously recorded measurement setups is often needed to be processed. These setups share some sensors in common, while the others are moved from one setup to the next. Like this detailed mode shapes of the structure can be obtained, mimicking lots of sensors, while in fact only a few sensors are used for the measurements. Recently, the “Pre Global Estimation Re-Scaling” (PreGER) for the Stochastic Subspace Identification (SSI) was proposed to obtain global modal parameters of the structure. It is a fully automated method that takes differences in the unmeasured background excitation levels between the setups into account, merges the data and does the global system identification. Like this, the different measurement setups can be processed in one step and do not have to be analyzed separately. In this paper, system identification results of the Humber bridge are presented, which is a challenging example as a big number of setups is available and special measures need to be taken to avoid numerical explosion of the computation. The results are compared to the PoSER approach (Post Separate Estimation Re-Scaling) with data-driven SSI.
KeywordsMode Shape Stabilization Diagram Ambient Vibration Vertical Mode State Transition Matrix
Unable to display preview. Download preview PDF.
- 1.Basseville, M., Benveniste, A., Goursat, M., Hermans, L., Mevel, L., van der Auweraer, H.:Output-only subspace-based structural identification: from theory to industrial testing practice. Journal of Dynamic Systems, Measurement, and Control 123(4), 668–676 (2001)Google Scholar
- 2.Brownjohn, J., Dumanoglu, A., Severn, R., Taylor, C.: Ambient vibration measurements of the humber suspension bridge and comparison with calculated characteristics. In: Proc. of the Institution of Civil Engineers (London), vol. 83, pp. 561–600 (1987)Google Scholar
- 3.Brownjohn, J., Magalh˜aes, F., Caetano, E., Cunha, A.: Ambient vibration re-testing and operational modal analysis of the Humber Bridge. Engineering Structures 32(8), 2003–2018 (2010)Google Scholar
- 5.Cunha, A., Caetano, E., Magalh˜aes, F.: Output-only dynamic testing of bridges and special structures. Structural Concrete 8(2), 67–86 (2007)Google Scholar
- 6.D¨ohler, M., Andersen, P., Mevel, L.: Data merging for multi-setup operational modal analysis with data-driven SSI. In: Proceedings of the 28th International Modal Analysis Conference (IMAC-XXVIII). Jacksonville, FL, USA (2010)Google Scholar
- 7.D¨ohler, M., Mevel, L.: Modular subspace-based system identification and damage detection on large structures. In: Proceedings of the 34th IABSE Symposium. Venice, Italy (2010)Google Scholar
- 8.D¨ohler, M., Reynders, E., Magalh˜aes, F., Mevel, L., Roeck, G.D., Cunha, A.: Pre- and postidentification merging for multi-setup OMA with covariance-driven SSI. In: Proceedings ofGoogle Scholar
- 9.the 28th International Modal Analysis Conference (IMAC-XXVIII). Jacksonville, FL, USA (2010)Google Scholar
- 11.Mevel, L., Benveniste, A., Basseville, M., Goursat, M.: Blind subspace-based eigenstructure identification under nonstationary excitation using moving sensors. IEEE Transactions on Signal Processing SP-50(1), 41–48 (2002)Google Scholar
- 12.16 Michael D¨ohler, Bijaya Jaishi, Laurent Mevel, and James M.W. Brownjohn 11. van Overschee, P., De Moor, B.: Subspace Identification for Linear Systems: Theory, Implementation, Applications. Kluwer (1996)Google Scholar