New and old bridge broadening rigid connection construction method for keeping traffic passage

The invention discloses a new and old bridge broadening rigid connection construction method capable of keeping traffic passage. On the premise that the traffic operation is not interrupted, upper structure flanges of new and old bridges are connected through a bonded steel plate, so the upper structures of the new and old bridges are stressed together, and under the action of a travelling crane live load, the vibration force and the vibration frequency of the new bridge and the old bridge are basically kept consistent, so that concrete for subsequent construction of the cross diaphragm of theupper structures of the new bridge and the old bridge cannot be stretched and extruded, the concrete quality of the cross diaphragm at the connecting part of the upper structures of the new bridge and the old bridge is ensured, and the steel bar embedding quality of the cross diaphragm is not influenced; in addition, the compressive strength and the bending and shearing strength of the connectingpart of the whole new bri