Load Testing and Model Updating of a Single Span Composite Steel-concrete Railway Bridge

Actual static and dynamic response of a newly constructed composite steel-concrete railway bridge with a single span of 32 m is investigated. The main objective of this investigation was to increase knowledge on the actual behavior of new innovative structure using field load testing and numerical simulation. Static and dynamic loads were applied by using two heavy locomotives 2M62 with the total load of 2328 kN. Five dynamic tests were conducted at speeds varying from 20 to 100 km/h. The outcomes of the static tests were maximum displacements of the bridge deck and that of dynamic tests were vibration characteristics, and in particular modal parameters such as vibration mode shapes, frequencies, damping ratios as well as dynamic amplification factors. Results of these investigations are presented in this paper.