Ghotoor is a monumental steel arch bridge in Iranian railway network. The bridge was built in 1970 and since then been operational. The bridge has seven spans of 29 meters, one span of 20 meters (steel Beam), and one giant steel arch of 223 meters. The bridge has been damaged during Iran-Iraq war, but was repaired and is now operational. The bridge accomodates a single track with an allowable axle load of 20 tons, and a speed of 60 km/h. The bridge is to be retrofitted by viscouse dampers, and the contractor consulted IMIRL for structural assessment of the bridge before and after retrofitting procedure. Bridge condition has been studied before installation of viscous dampers. Viscouse dampers have now been installed and the second phase of tests are to be carried out in the near future.