Due to the specific conditions of the passage of the railway track on the low -powered part of the Volga -Akhtubinsky floodplain, as well as in accordance with the design assignment, the high -altitude dimensions from the RSU -19.75 m are prescribed: in the divorced span to the raised span 10.35 m, in the inpatement spans with a length of 110 m, 3.56 m, which is no lower than the corresponding dimensions near the railway bridge. In accordance with the act of choosing sites for the construction of a two -way bridge with a divorce flight, the target of the bridge crossing was adopted 50 m downstream of the existing bridge over the Buzan River. When developing the main design solutions, several options for the location of the bridge transition. 4 different options for the location of the alignment were studied, including above the axis of the existing bridge parallel to it at distances of 20, 50, 100 m or more, the same – below the axis of the existing bridge and parallel to it, higher and lower than the axis of the existing bridge with the aim of it for the purpose Glotting of the bridge transition route. All possible options for the alignment were considered in conjunction with options for the railway line on the approaches, regardless of the possible scheme of the bridge, but taking into account the boundary conditions, the length of the reconstructed section on the approaches, the volume of work, cost, technology of construction, the conditions of further operation of navigable requirements, payroll and other factors. In the options with the location of the axis of the highway above the existing bridge, attractive from the point of view of improving the operational characteristics of the track in the plan, the length of the reconstructed section increased sharply and the need arose to reorganize the overpass over the tracks, which increased the total cost of the transition and the construction time.
