Ballast bed track construction and maintenance device and railway car

The invention belongs to the field of rail transit, and particularly relates to a ballast bed track construction and maintenance device. The device comprises a rotating mechanism, a combined arm and a hydraulic cylinder, wherein the rotating mechanism is connected with a railway car through a movable connecting piece and rotates relative to the railway car; the rotating mechanism comprises a first sliding block, a second sliding block and a mounting table with a sliding groove, and the first sliding block and the second sliding block are arranged in the sliding groove and move relative to each other along the sliding groove; one end of the combined arm is hinged to the first sliding block, one end of the hydraulic cylinder is connected with the combined arm, and the other end of the hydraulic cylinder is connected with the second sliding block. The railway car comprises the ballast bed track construction and maintenance device. The ballast bed track construction and maintenance device is convenient to install