A PARTNERSHIP between Railtrack and geotechnical contractor May Gurney recently completed rapid stabilisation of a an embankment on the East Coast Main Line near Hartlepool in north-east England.
In early November, a 380m long section of the embankment on a remote part of the Leeds to Newcastle line dramatically failed, leaving 100m of track hanging in mid air.
The slip was caused by extreme flooding in the area at the end of last year.
The team was asked to find a solution which would reinstate the embankment and reopen the line to both up and down traffic by Christmas.
Consultant Hyder's solution was to move the area of track affected by the slip to the other side of the embankment and reposition it alongside the existing track, placing crossovers at each end of the failed section.
This was possible because both the up and down lines lie on one side of the wide embankment. Jarvis rail carried out the track work, allowing the lines to be reopened with speed restrictions by December 23, while the failed embankment was being repaired.
Stabilisation involved replacing the failed embankment material, covering it with a heavy wire mesh and installing over 1700 soil nails.
Most of the soil nails were installed with small rigs lowered by hand and operated via rope access. Only the top and bottom rows were installed using large soil nailing rigs where access permitted.
The team worked 24 hours a day, seven days a week from 14 December to 23 January 2001, with only Christmas Day and Boxing Day off, to achieve the deadline required by Railtrack. This allowed the rail operator to lift speed restrictions by 27 January.