Ground Freezing

Ground Freezing

Artificial ground freezing is a technique that converts in situ pore water to ice through the circulation of a chilled liquid via a system of small-diameter pipes placed in drilled holes.

The ice acts to fuse the soil or rock particles together, creating a frozen mass of improved compressive strength and impermeability. It is most advantageous where both support of excavation and groundwater cut-off are required, and it is performed at significant depth or in difficult ground conditions that preclude the safe use of other more commonplace techniques. Deep shafts, cross passages, tunnels with mixed face or difficult ground conditions, and other underground structures are prime candidates for ground freezing.