الفهرس | Only 14 pages are availabe for public view |
Abstract This paper aims to investigate the structural behavior of railway steel bridges due to track defects, such as abnormalities on rail or wheel surface as rail corrugation, rail wear or breakage, wheel flats, non-grinding weld and rail joint. Two categories of dynamic models were established by using the finite element software ABAQUS, which simulated the structure as a train-track-bridge (TTB) interaction model. Benha’s railway steel-truss-bridge was used in this study. The part simulated of the bridge’s superstructure is made of 2 spans, with a total span of 124.8 meters. The train runs through open deck floor (i.e. non-ballasted track). The track is fixed directly to the bridge stringers and cross girders. The first model was created in order to check the validity of the simulation used for the chosen bridge. This was done by comparing the output of the model against the field measurements which were performed by the Housing and Building National Research Centre (HBRC) in Egypt. While the other model, however, was created so as to simulate the defects of the track. That’s to say the models in the TTB category were established in order to study the effects of the response (acceleration and strains of the bridge’s stringers and cross girders) and also to predict the dynamic-amplification-factors for each type of simulation. The results from the TTB models, related to the simulation of the track defects, were compared against those written in both Euro and UIC codes. On the other hand, the effect of train speed on the bridge responses with and without considering the track defects are investigated. |