Experimental Modal Analysis of the Footbridge across Vltava River in Prague Damaged by Flood in June 2013

Abstract:

The investigated footbridge across Vltava River in Prague was built in 1984. Almost the entire footbridge structure was overflowed by the extreme flood in August 2002 and the substantial part of the footbridge deck was overflowed afterwards by the great flood in June 2013 again. A significant damage on the footbridge deck was found out by a visual inspection of the load-bearing structure of the footbridge after the second flood. The basic objective of the performed experimental modal analysis was the initial experimental reliability verification of the obviously damaged footbridge structure. The measured natural frequencies and modes were compared with results of the several dynamic tests which were performed regularly during the lifetime of the footbridge. The localization of potential invisible damages was carried out. The recommendations for the range and the arrangement of the static load test, which was performed afterwards for fundamental reliability assessment of a footbridge structure, were made on the basis of the evaluated results of the experimental modal analysis.

• Periodical: Applied Mechanics and Materials (Volume 617)
• Pages: 3-6
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.617.3
• Online since: August 2014
• Authors: Michal Polak*, Tomáš Plachy, Jiří Maca
• Keywords: Damage, Experimental Modal Analysis, Flood, Footbridge, Natural Frequency, Natural Modes

References

[1] M. Pirner, O. Fischer, Studijní dynamická zkouška lávky v Praze – Troji (in Czech) (Experimental Dynamic Study of a Footbridge in Prague - Troja ) – expert report, Institute of Theoretical and Applied Mechanics Academy of Sciences of Czech Republic, Prague, (1997).

[2] M. Polák, T. Plachý, Dynamická zatěžovací zkouška stávající lávky pro pěší přes řeku Vltavu v Praze – Troji (in Czech) (Dynamic Load Test of an Existing Footbridge across Vltava River in Prague - Troja ) – expert report, Czech Technical University in Prague Faculty of Civil Engineering, Prague, (2010).

DOI: 10.17973/mmsj.2022_10_2022120

[3] T. Plachý, M. Polák, Damage detection and localisation on reinforced concrete slabs based on modal analysis, in: L. Collini (Ed. ), 22nd Danubia-Adria Symposium on Experimental Methods in Solid Mechanics, DAS 2005, University of Parma / Ingegneria Industriale, Parma, 2005, pp.247-248.

[4] T. Plachý, M. Polák, Experimental Modal Analysis of the Footbridge across Bečva River in Přerov, in: M. Růžička, K. Doubrava, Z. Horák (Eds. ), Proceedings of the 50th Annual Conference on Experimental Stress Analysis (EAN 2012), Czech Technical University in Prague Faculty of Mechanical Engineering, Prague, 2012, pp.327-332.

DOI: 10.17973/mmsj.2022_10_2022120