The utility model relates to a flatcar device about railway rails especially relates to the polyurethane solidification railway roadbed operation dolly device of track flatcar from top to bottom, including getting on or off the bus track 1, still including track lift and the adjusting device 5 of getting on or off the bus, the track 1 of getting on or off the bus is installed on this lift and adjusting device 5. The utility model discloses a track of getting on or off the bus goes up and down and adjusting device 5, can realize getting on or off the bus the track 1 when putting down, and the overlap joint is to the circuit track 2, as the track of the quick upper and lower track flatcar of operation dolly, when packing up, through 4 lockings on the track support on locking device 11 and the track flatcar 3, walk the line along with track flatcar 3. The operation dolly can be realized and track plan track flatcar is from top to bottom followed.