Computational & Technology Resources
an online resource for computational,
engineering & technology publications
PROCEEDINGS OF THE NINTH INTERNATIONAL CONFERENCE ON COMPUTATIONAL STRUCTURES TECHNOLOGY
Edited by: B.H.V. Topping and M. Papadrakakis
The Old Steel Bridge: Dynamic Analysis Utilization for Estimating the Bridge Structure Ultimative Capacity
J. Bencat and D. Papán
Department of Structural Mechanics, Faculty of Civil Engineering, University of Zilina, Slovakia
, "The Old Steel Bridge: Dynamic Analysis Utilization for Estimating the Bridge Structure Ultimative Capacity", in B.H.V. Topping, M. Papadrakakis, (Editors), "Proceedings of the Ninth International Conference on Computational Structures Technology", Civil-Comp Press, Stirlingshire, UK, Paper 284, 2008. doi:10.4203/ccp.88.284
Keywords: traffic effects on structures, FEM, in situ experimental tests, spectral and correlation analysis, bridge static and dynamic loading tests, structure diagnostics, natural frequencies and modes.
A large number of existing bridges need to be rehabilitated due to increasing traffic and/or loading requirements. A procedure is presented for estimating the the ultimate capacity of a steel bridge over the Danube river in Bratislava: the Old Bridge built in 1945. The bridge load bearing structure is created partly by continuous truss main beams (spans 2,3,4) and partly by single beams (spans 0,1,5,6). The bridge deck is composed of a steel grate system (cross and longitudinal beams) bearing the reinforced double-T prefabricated road panels.
The development of a simplified finite element model (FEM) and basic modal parameter calculations preceeded the bridge experimental investigations via static and dynamic in situ loading tests, so that the main assumptions adopted in the FEM were assessed through the comparison between measured and predicted dynamic and modal parameters of the bridge structure . Ambient vibration tests were also carried out to determine the service dynamic response characteristics of the bridge structure to compare with relevant standard criteria. The bridge structure computational model was then optimized using structure variable values (mainly steel structure joint masses and corrosion grades) to achieve the minimum differences between the experimental and theoretical results. The calibrated FEM with the optimal combinations of the variable values mentioned were defined and finally used for structural calculations and the strengthening design of the bridge structure .
purchase the full-text of this paper (price £20)