Demolition and reconstruction construction method for removing old bridge of overline arch bridge by using new bridge

The invention discloses a dismantling and rebuilding construction method for dismantling an old bridge by using a new bridge for an overline arch bridge, which comprises the following steps of: S1, dismantling the old bridge, and only retaining an arch rib of the old bridge; s2, parts of the upper portions of bridge abutments on the two sides of the old bridge are dismantled; s3, temporary steel pipe supports are erected on bridge abutments on the two sides of the old bridge, and longitudinal beams of the new bridge are hoisted on the temporary steel pipe supports; s4, a plurality of hanging beams are arranged on the longitudinal beams of the new bridge, and an electric hoist and a steel wire rope are arranged below each hanging beam; s5, hoisting the arch rib by using a steel wire rope and an electric hoist, and cutting and removing the arch rib of the old bridge section by section; and S6, permanent supports are installed on the bridge abutments on the two sides, longitudinal beams of the new bridge are hoi