PURPOSE: To enhance the working efficiency of flattening the ballast on a track bed by picking up surplus ballast from the track bed by a ballast pickup mechanism, storing it once in a storage vessel, and scattering it on the portion lacking in ballast.

CONSTITUTION: A machine frame 2 supported by a track 3 is equipped with a ballast pickup mechanism consisting of a sweepup type conveyor mechanism 13 fitted with an inclined belt conveyor 15. A storage vessel 18 for ballast is installed furnished with a cast-in opening 24, and on its bottom plate, or in lieu thereof, a belt conveyor 19 is installed, wherein the discharge position 23 is located near the cast-in opening 24. The surplus ballast on the rack bed is picked up by the pickup mechanism and once stored in the storage vessel 13. After moving the truck 3, the ballast in the vessel 13 is led to the opening 24 by the belt conveyor 19 and scattered on the track bed portion lacking in ballast.