"2311-9020" . . . . . "[65F28C36ACCE]" . . "Kar\u00E1sek, P." . . "Proceedings of the IX International Conference on Structural Dynamics, EURODYN2014" . "Plach\u00FD, Tom\u00E1\u0161" . . "Modal Analysis; Footbridge; Damage detection; Bridge dynamics; Natural frequencies; Mode shapes"@en . . "In the last two decades, the Czech Republic has been hit by great floods, causing damage on many bridges. An important question, whether the bridge has to be demolished, or can be used under certain operating conditions, often arises. The investigated footbridge across the Be\u010Dva River in P\u0159erov was built in 1983. During the extreme flooding the footbridge deck was overflowed by water, which caused a significant increase of the main span permanent deflection, about 1 m in the vertical direction compared to the state before flooding. The footbridge was closed for all users immediately. During the assessment of the footbridge structural integrity, it was decided to carry out an experimental modal analysis of the structure. The results of the modal analysis were compared with the results obtained on the footbridge in 1983. It was found that the dynamic behavior of the footbridge changed significantly. Especially, the basic natural mode has totally changed its shape. Finally, the measured modal characteristics were compared with the values provided by the Finite Element (FE) model. The comparison confirmed that the big changes in natural mode shapes were caused by the increase of the permanent deflection of the footbridge. The agreement between the newly measured and calculated natural mode shapes was high, however, small differences were found out and two suspicious areas were detected. The behavior of the real structure in these areas was different from the model predictions, and their detailed investigation was recommended because of a possible damage. One of these areas was located in the vicinity of the supporting pier. The experimental analysis revealed bigger flexibility of the pier in the horizontal transversal direction than the FE model predicted. The consequent inspection of the footbridge revealed a crack in the area of the concrete hinge joint." . "29689" . . "http://paginas.fe.up.pt/~eurodyn2014/CD/papers/359_MS13_ABS_1111.pdf" . . "3"^^ . "Faculdade de Engenharia da Universidade do Porto" . "RIV/68407700:21110/14:00224395!RIV15-TA0-21110___" . "978-972-752-165-4" . . . . . "Modal Analysis of a Footbridge Damaged by Flood" . . "21110" . "2"^^ . "2014-06-30+02:00"^^ . . "RIV/68407700:21110/14:00224395" . "8"^^ . . "Modal Analysis of a Footbridge Damaged by Flood"@en . "Modal Analysis of a Footbridge Damaged by Flood" . "In the last two decades, the Czech Republic has been hit by great floods, causing damage on many bridges. An important question, whether the bridge has to be demolished, or can be used under certain operating conditions, often arises. The investigated footbridge across the Be\u010Dva River in P\u0159erov was built in 1983. During the extreme flooding the footbridge deck was overflowed by water, which caused a significant increase of the main span permanent deflection, about 1 m in the vertical direction compared to the state before flooding. The footbridge was closed for all users immediately. During the assessment of the footbridge structural integrity, it was decided to carry out an experimental modal analysis of the structure. The results of the modal analysis were compared with the results obtained on the footbridge in 1983. It was found that the dynamic behavior of the footbridge changed significantly. Especially, the basic natural mode has totally changed its shape. Finally, the measured modal characteristics were compared with the values provided by the Finite Element (FE) model. The comparison confirmed that the big changes in natural mode shapes were caused by the increase of the permanent deflection of the footbridge. The agreement between the newly measured and calculated natural mode shapes was high, however, small differences were found out and two suspicious areas were detected. The behavior of the real structure in these areas was different from the model predictions, and their detailed investigation was recommended because of a possible damage. One of these areas was located in the vicinity of the supporting pier. The experimental analysis revealed bigger flexibility of the pier in the horizontal transversal direction than the FE model predicted. The consequent inspection of the footbridge revealed a crack in the area of the concrete hinge joint."@en . "Porto" . . "Porto" . . "P(TE01020168)" . "Modal Analysis of a Footbridge Damaged by Flood"@en . . "Pol\u00E1k, Michal" .