BarChip was Chosen as the Preferred Fibre for Shotcrete Reinforcement in Complex Ground Conditions at Lyon-Turin Base Tunnel

BarChip fibre is reinforcing the shotcrete ground support at the Lyon-Turin Base Tunnel SMP4 site, including the 1.4 km conventionally excavated tunnel through a coal seam.

The Lyon-Turin high speed rail is a future building infrastructure project on a scale rarely seen. 270 km of freight and passenger rail lines, 220 km/h operating speed and the connection of the French and Italian rail systems at an estimated cost of 25 billion Euros. The crown at the centre, the twin-tube 57 km Mont Cenis Base Tunnel, crossing up to 2,000 m underneath the alps from Susa in Italy to Saint-Jean-de-Maurienne in France.

Made up of 4 sections, the SMP4 site marked the first excavation of the main rail tunnels. Sections 1 and 4 comprised the construction of the TBM launch and disassembly chambers at the foot of the previously built Saint-Martin-la-Porte and La Praz access adits. Section 2 saw TBM Frederica drive the first 9 km in the East bound tunnel to the La Praz Chamber, with the breakthrough occurring in 2019.

The 3rd section was broken into two parts. Part 3a required the construction of a 1.8 km reconnaissance gallery from the descent of the Saint-Martin-la-Porte access adit. The tunnel bypasses a coal seam before rejoining the main tunnel, serving as an exploratory and secondary access tunnel. Part 3b involves the construction of a 1.4 km tunnel, beginning from the end of the bypass tunnel. 3b passes through the coal seam to connect with the western end of the previously driven access tunnel.

In April 2022, workers broke through the 3b tunnel into the existing 9 km Frederica drive, marking the completion of the first 10.5 km of the Lyon-Turin Base Tunnel. After significant trials and on-site testing, BarChip was chosen as the preferred fibre for shotcrete reinforcement in ground control solutions at the SMP4 site.

Lyon-Turin has now completed 18% of planned tunnelling works and is scheduled for completion in 2032. BarChip is proud to be part of this great project and look forward to providing support to future development in the years to come.