Dynamic Modal Assessment of Old Reticular Steel Railway Bridges Undergoing Fatigue Deterioration

Abstract:

To reduce traffic disruption due to a live-cycle and seismic damage it is necessary to study the causes in infrastructures and bridges. When we talk about steel structures and in particular steel bridges, we know that they are very flexible and consequently easy to identify by ambient vibration methods. In a collaborative project between the University of Padua and the Italian Railway Authority, two old reticular steel bridges (1920) were subject to in-situ structural identification, demolition and consequent laboratory fatigue tests. On account to their similarity it was possible to acquire dynamic data for several days by using the same acquisition logger and 12 acceleration sensors After the data of the two analyzed reticular bridges have been filtered, accurate vibrating modes were identified by using both time and frequency domain techniques and the results were outstanding. In order to use best-fitted material characteristics in the elements of the structures, destructive and non-destructive tests were executed. The results permitted to realize very accurate finite element models and calibrate them for successive fatigue scenarios by comparing laboratory and numeric tests.

• Periodical: Applied Mechanics and Materials (Volumes 361-363)
• Pages: 1442-1445
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.361-363.1442
• Online since: August 2013
• Authors: Kleidi Islami, Giovanni Tecchio, Claudio Modena
• Keywords: Modal Analysis, Output-Only Techniques, Reticular Steel Bridges

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