Bretagne-Pays de Loire high-speed line, France

Compaction grouting under railway backfills

As part of the construction of the Bretagne - Pays de Loire high-speed line, Menard was requested to stabilise the ground under the railway backfill.

A drilling campaign showed that the area to be treated was made of fossilised karst filled with sand, which made the ground extremely loose and sub-consolidated.

Menard prescribed a solution consisting of compaction grouting. The method was implemented in two phases: the boring and the installation of grouting tubes, then the grouting of mortar over the whole height of the boreholes.

The grouting was carried out following a precise meshing at depths varying between 5 and 15 m.