The pieces of the large tunnel boring machine that will excavate the tunnel of the S19 motorway between Rzeszów Południe - Babica (Poland), are already in the municipality of Babica, where assembly has begun to begin work soon.

The pieces left months ago from Spain after a long period of route planning. During the logistically complex journey, the load-bearing capacity of all the structures through which the parts of the tunnel boring machine had to pass had to be taken into account, among many other details. However, there were certain sections where the machine’s passage required some design changes. In Rzeszów, under the railway viaduct, 36 cm of asphalt had to be cut back.

The assembly of these pieces has already begun and the total assembly is expected to last three months. Once assembled, the machine will weigh 4,000 tons and be 112 meters long with a cutter wheel diameter of 15.2 meters.

The tunnel boring machine was “baptized” Karpatka after a virtual vote in which more than 9,000 citizens participated.

Reconditioning of an old tunnel boring machine

The tunnel boring machine owned by ACCIONA was refurbished at the company’s Technology Park in Noblejas (Toledo) to adapt it to the needs of this complex project.

The Construction Support Department refurbished an old EPB TBM that was used more than 16 years ago in the M-30 underground work in Madrid, where it set the world record for excavation diameter in its year of manufacture.

To refurbish this TBM, the two cutting wheels of the old machine had to be reduced to one.  In addition, some improvements have been introduced, such as the replacement of the mortar with a two-component system, the incorporation of a rapid unloading system for the segments, or the assembly of the ring in semi-automatic mode.

Other enhancements include an innovative geological prediction tool that allows data to be collected from the face without drilling.