The bridge on Km1035+000 of Iranian railway network is steel truss railway bridge. It consists of 3 spans of 80 meters, and two smaller spans of 60 meters, totaling a length of 360 meters. The bridge is located in a curved section of the track with a radius of 700 meters, and a longitudinal slope of 12‰. The bridge accomodates a couple of tracks with an allowable axle load of 25 tons. The two tracks are built within 10 years of each other. The old track has an allowable speed of 60 km/h, while that of the new track is 120 km/h. The ballastless superstructure consists of UIC60 rails, wooden sleepers, and screw fasteners. Both insulated and welded rail joints could be spotted on the bridge.
Since the costs of maintenance are quiete high, the maintenance contractor proposed to replace the superstructure of the bridge with slab-track. In this regard, IMIRL has carried out dynamic load tests on the bridge to assess its structural response and study the optimized maintenance strategy for the bridge, considering long-term costs.
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