Underground Construction

In the construction of underground spaces, such as tunnels, underground stations and parking garages, the geotechnical properties of the soil, the ground water and the workability of the soil are boundary conditions for the design and for the choice of construction methods.

Until recently no bored tunnels were driven in The Netherlands. In the early nineties this changed with the construction of the second Heinenoord tunnel under the river Meuse. GeoConsult made the geotechnical models in the pre-design stage for this tunnel.

More bored tunnels followed: the tunnel under the Westerschelde, the sea entrance of Antwerp, the Botlek railway tunnel, the tunnel which is part of the High Speed Rail link Amsterdam-Brussels, and the North-South Metrolink in Amsterdam which has recently been started. GeoConsult made a variety of contributions: site investigation design, geotechnical models, research of borefront stability, application of foam, gradations of bored materials, swelling behaviour of clays and the characteristics of bored materials in over consolidated clays.

One of the innovative constructions in The Netherlands is a circular shaped parking garage built in the city of Groningen. This construction is made in glacially over- consolidated clays. The circular wall is self supporting as a result of arching and is constructed as a diaphragm wall. GeoConsult provided the advice on the horizontal, anisotropic, soil pressures and conducted the research on the clay and the swell and floor heave of the open base of the garage.