Rail layered steel box girder

The present invention discloses a well-layered iron girder, which includes top and bottom slab box girder, box girder plate located below the central roof box girder, box girder box beam between the top and bottom with a support structure, the support structure for the box-girder structure; lateral ends with a box beam ceiling of the vertical side webs extending between the lower end and ends with a bottom slab ipsilateral side web edge bottom, box beam ceiling, web side, bottom side and bottom slab surrounded by a trapezoidal box cavity. The present invention is based on the conventional steel box girder on the increase in cross-sectional height, the railway may be disposed inside the steel box girder; a support structure and a box girder box beam ceiling and floor between the use of truss structure, monolithic than steel box girder save steel.