Underground is the solution for the future

Pipe jacking and microtunnelling

Pipe jackings can be driven in a straight line or along a curved route with horizontal and/or vertical curves, or a combination of both. We use various types of tunnel boring machines for this: slurry shields, mix shields, with mechanical front support, earth pressure balance shields,… adapted to the geology and the environment.

From a traffic, social-economic and ecological perspective, pipe jacking is ideal for installing sewer pipes and collectors. The pipe jacking technique is also the recommended method for passing underneath railways, waterways and motorways. The implementation of PC-controlled automatic bentonite injection units, combined with well-placed intermediate jacking stations, allows pipe jackings to lengths of up to 2000 to 3000 m.

Inaccessible tunnels are bored using remote controlled microtunnelling machines from prefabricated drive shafts that can be equipped as access chambers after the boring.

They have a precision in height and direction of a few centimetres, over distances of up to 400 to 500 m, thanks to the innovative computer-driven measurement systems with motorised laser theodolites.

Segment tunnelling

Segment tunnelling is a technique used throughout the world in which the tunnel boring machine (TBM) is equipped with an erector that constructs the tunnel rings immediately after drilling: the TBM is pushed into the ground by jacks and moves like a caterpillar, while just behind it the tunnel segments are immediately installed and secured with underground injections.

The tunnel boring machines (TBMs) are analogous in design philosophy and operation to the aforementioned TBMs for pipe jacking. This technique is appropriate for traffic tunnels with larger sections (larger than 4 m) and in specific geological conditions.