Bridge on Km 487+800 is a railway masonry arch bridges with 10 spans and has been operational for about 75 years. The bridge accomodates a single track of 20 tons. The bridge consists of three long spans of 21.5 meters, and seven spans of 10 meters, totaling a length of 270 meteres for the bridge. Track's superstructure consists of U33 rails, wooden sleepers, and 'K' fasteners. Rail joints on the bridge are either bolted or welded. Maximum operational speed of the bridge is 60 Km/h.
Summary of results:
The bridge is tested due to application of operational loading patterns of the bridge in serviceability and ultimate limit states. Moreover, seismic assessment of pier and arch sections are carried out. According to test results, it is observed that in SLS, keystone of 10 meters spans are in critical condition and cracks may propogate in these points, but the ring is capable of handling the load. Results of ULS analyses suggest that in the load factor of the bridge is 1.25, which shows that archs are capable of withstanding standard loading of desing codes. Seismic assessment results suggest that in longitudinal and lateral earthquakes, archs and piers require retrofitting, respectively.
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