Studies concerning the optimization of the modal analysis of the Bechtel’s viaducts – calculus of natural frequencies and eigenvalues
Journal Title: Romanian Journal of Acoustics and Vibration - Year 2011, Vol 8, Issue 1
Abstract
This paper proposes an approach of the experimental study of the dynamics of a reinforced concrete bridge made by a number of twenty U beams and beared by eighty identically neoprene supports (four bearings for each concrete beam). The experiments were made in site on Transylvania highway, on the viaduct situated on km 29+602,75 - km 29+801,25 by the specialists from Vibration and Acoustic Laboratory of the Research Institute for Construction Equipment and Technology - ICECON S.A. Bucharest with the help of the Research Center of Machines, Mechanic and Technological Equipments – MECMET from Dunarea de Jos University of Galati. The vibrations of the bridge were caused by passing with different speeds of a forty tons truck over an obstacle mounted on the bridge surface. The experimental data were acquainted on three channels (accelerations on the axis x, y and z) by a four channel data acquisition interface from National Instrument (NI 9233) through the USB port of a PC workstation. The experimental data were processed by a adequate calculus programme developed on ICECON S.A. Bucharest on the basis of LabView® ver. 8.5 from National Instruments.
Authors and Affiliations
Leonidas Sakalauskas, Nicuşor Drăgan, Ovidiu Vasile
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