METHOD TO RESTORE UNDERBALLAST LAYER OF RAILWAY TRACK Russian patent published in 2011 - IPC E01B27/20 

FIELD: construction.

SUBSTANCE: method to restore an underballast layer of a railway track includes removal of old crushed stone to clean earth bed, filling a protective underballast layer onto the cleaned earth bed and its compaction, filling new crushed stone. The protective underballast layer is compacted by a track machine in two stages. At the first stage compaction is executed with application of assembled rails and sleepers with epure of sleepers making 1840 pcs/km. At the second stage compaction is executed with application of assembled rails and sleepers with epure of sleepers making 2000-2100 pcs/km. Between the first and second stages of compaction the protective underballast layer is moistened to obtain moisture of not more than 6%. Compaction is carried out at the speed of the track machine of 0.8-0.9 km/hr. At least one additional compaction of the protective ballast layer is carried out at each stage.

EFFECT: increased extent of the protective underballast layer compaction.

4 cl, 5 dwg