Sarens recently transported a 1,500-tonne tunnel boring machine (TBM) for Line 17 of the Grand Paris Express, a project led by Société des grands projets. The operation involved moving the 100-meter-long equipment over a distance of 700 meters from its assembly platform to the starting point of excavation.
The TBM, comprising a 1,000-ton shield and a 500-ton trailer, was moved in a single operation. This approach, requested by the customer Razel-Bec, enabled the project to be carried out to a tight schedule and within the constraints of the site, located at the end of an airport runway. The operation began with the lifting of the shield using the Sarens Climbing System CS250, which raised the whole structure by 2.5 metres. Once stabilized, the TBM was positioned on 34 lines of SPMT axles: two sets of 17 lines at the front, and two sets of 10 lines at the rear, the latter providing braking management. An additional SPMT was integrated at the rear to reinforce braking capacity over a 300-meter stretch with a 6% gradient. This configuration enabled the complete TBM to be moved all the way to its final position.
Once at its destination, the TBM was lowered back down using the same CS250 hoisting system, and the last 20 m were driven using the Sarskid 400, a controlled sliding device for precise positioning. The operation involved two sets of 17 SPMT axle lines placed under the shield, each capable of supporting up to 48 tonnes per axle, as well as two sets of 10 axle lines at the rear, dedicated to braking control. The CS250 system was used for lifting and lowering the TBM, while the Sarskid 400 system was used for final positioning, guaranteeing precise adjustment. This transport was an essential step in keeping the project on schedule and enabling excavation work to start on schedule.
This move enabled the TBM to be positioned ready to start digging the 6-kilometer tunnel to the future extension of line 17 to Charles-de-Gaulle airport.
Sarens, in coordination with Razel-Bec, was responsible for the planning and implementation of this operation, integrating the technical, safety and deadline requirements specific to the Grand Paris Express worksite.
