Reinforcing structure for construction of existing railway underneath pass frame bridge

The utility model discloses a reinforcing structure for construction of an existing railway underneath passing frame bridge, which is based on the existing railway under a 12% o large longitudinal slope and a small-radius horizontal curve R = 300m, and comprises a plurality of frame bridges, and a space is reserved between every two adjacent frame bridges. The longitudinal lifting beams are laid at the bottom of the existing railway in the direction of the existing railway, the transverse lifting beams are supported below the existing railway, the transverse lifting beams are fixed between the longitudinal lifting beams and the existing railway and located between two adjacent sleepers of the existing railway at the same time, and the longitudinal depth of the transverse lifting beams is larger than that of the sleepers; a plurality of buttress groups for supporting the longitudinal lifting beams are arranged at the bottom of the existing railway; the reinforcing structure is simple, the structural stability