Students were requested by Metro-North Railroad to design a ballast bridge to replace the existing open deck bridge spanning Indian Harbor in Greenwich, CT and to design superstructure for replacement of Steamboat Road Bridge. The project also included developing the construction process, schedule, and cost estimate.
The goal of this project is to design a ballast bridge to replace the existing open deck bridge spanning Indian Harbor in Greenwich, CT. The original bridge was built in 1895 and reconstructed in 1943. This bridge supports 4 rail lines and has a span of 60 feet. Inspection of the open deck bridge indicated that it was in fair condition. A construction schedule and cost estimate were performed in addition to redesigning the superstructure for a ballast deck bridge
The girder selected for the ballast bridge has a flange width of 18 inches and a web of 49 inches. For safety reasons, the new design uses four girders instead of the existing two girder super structure. Abutments should be reinforced and stabilized by adding soil nails where applicable. A walkway on one side of the bridge was also designed for workers safety when crossing the bridge.
The superstructure for the Steamboat Road Bridge was designed using the same methodology as the Indian Harbor Bridge. The girder selected has a flange width of 18 inches and a web of 30 inches.