Underground works :
for the most demanding projects
Underground worksites are very technical, often complex, always unique and subject to stringent preparatory phases. They have been one of Eiffage Génie Civil's specialist fields for many years. As a trusted partner, we support and assist our customers from project inception to completion.
Underground construction : a case for the specialists
Road, rail and industrial tunnels, sewers and hydraulic facilities (with their tunnels, shafts, chimneys and caverns) : Eiffage Génie Civil brings its expertise to all project configurations and in all contexts, including new structures, upgrading, loading gauge provision and safety solutions.
Our teams offer a complete range of techniques including TBM boring and blasting by conventional methods or with road-headers. They have full control on all types of firm and soft ground and bedrock.
When agility rhymes with operational excellence
Our dedicated teams manage the specific risks associated with all types of worksite, whether on road, rail or industrial structures. They are able to operate whatever the terrain, environment or technique required.
Eiffage Génie Civil boasts numerous specialized teams of engineers, technicians, geotechnicians, tunnel boring machine operators, miners, etc., all of whom know how to adapt their methods to the environments encountered.
80 years of history, and so much more to write...
Multiple skills and shared pride... Highly technical and always unique, in environments as stimulating as they are rewarding, underground work has been a specialty of Eiffage Génie Civil for over 80 years. Watch this film to relive the milestones in our history!
Some prestigious underground projects
VL8 collectorBatch 02 - Paris Region< class="name">VL8 collector>
The VL8 collector will reinforce the wastewater network, preventing untreated water from being discharged into the natural environment and ensuring the bacteriological quality of the Seine for bathing during the Paris Games.
Toulouse subwayToulouse< class="name">Toulouse subway>
Eiffage, acting through its subsidiary Eiffage Génie Civil, in a consortium with NGE, will be responsible for the design and construction of an 8.416 km tunnel, 6 stations, 5 ancillary structures at intersections and a connecting structure to the maintenance site. The contract also includes the construction of 9 shafts connecting the shafts to the tunnel.
Line 14Lot GC03 – Paris region
As part of the Grand Paris Express project, the RATP awarded Eiffage Génie Civil in consortium the works on lot GC03 of the future Line 14 South which will link Olympiades metro station to Orly Airport. The 365-million-euro contract involves building a 4-km tunnel through the municipalities of Thiais, Rungis, Chevilly-Larue and L’Haÿ-les-Roses. This contract also provides for engineering construction in 3 stations : Chevilly « Trois-Communes », M.I.N. Porte de Thiais and Pont de Rungis, and 3 ancillary structures.
The works involve deploying 110,000 m³ of concrete and excavating 520,000 m³ of land, requiring a TBM. 420 people will be mobilized for the duration of the project.
Line 14 South, 14 km long underground, will benefit over 260,000 inhabitants of the Val-de-Marne and Essonne departments. After commissioning, it will offer connections with metro Line 7, suburban train (RER) C and tram 7. It will also link up with Line 15 South and Grand Paris Express Line 18. The Line 14 extension to the south will provide a rapid link between Paris and Orly Airport while serving dense residential zones and some of the urban area’s major centres and facilities, like Rungis Market or Gustave Roussy Institute hospital.
Line 15Lot T2B - Paris region
Line 15 - Lot T2B
The Société du Grand Paris awarded Eiffage Génie Civil in consortium the works on lot T2B of Grand Paris Express Line 15 South in the Val-de-Marne, linking Bry-Villiers-Champigny and Créteil l’Échat stations.
This 795-million-euro contract (435 million euros for Eiffage) includes the digging of a 7.2 km twin-track tunnel with an inside diameter of 8.70 m, the building of 7 inter-station ancillary structures and one ancillary structure for the future link with Line 15 East, and the construction of 3 stations : Bry-Villiers- Champigny, Champigny Centre and Saint-Maur Créteil.
The works will require two TBMs (Camille and Aïcha) and will mobilize up to 800 people.
Line 16Line 16 - Lot 1 - Paris region
Line 16 - Lot 1
The Société du Grand Paris awarded Eiffage Génie Civil, at the head of a consortium, the works included in Lot 1 of Grand Paris Express Line 16, linking Saint-Ouen to Aulnay and Le Bourget, in the Seine-Saint-Denis department. These works will ensure the connection with Line 14 and the construction of the first kilometres of Lines 17 and 15 East.
The 1.84 billion-euro contract (1.71 billion euros for Eiffage) involves digging over 19 km of tunnel, building 18 ancillary structures, laying tracks and fitting catenaries and linear equipment, and constructing 5 stations : Stade de France, La Courneuve Six-Routes, Le Bourget RER, Le Blanc-Mesnil, and Saint-Denis Pleyel, which will be the biggest station on the Grand Paris Express (250,000 passengers per day).
This huge project, which involves deploying 700,000 m³ of concrete and excavating 2,600,000 m³ of land, will require the use of six TBM (Armelle, Valérie, Bantan, Inès, Dorine and Sarah).
It will mobilize over 1,500 people at project peak and generate around 6,000,000 hours of work, including 500,000 hours on insertion programmes (work experience).
RER E EoleRER E - Paris region
Eole - RER E
Extension of Eole – RER Line E
The project, carried out in a consortium with Bouygues (leader) and Razel-Bec, includes 6.1 km of tunnel and the construction of a station under the Porte Maillot.
Janots GalleryProvence, Alpes, Côte d’Azur
The Janots tunnel, bored by TBM Augustine – 135 m long and 3.50 m in diameter – transports water from the Marseille Canal between Cassis and La Ciotat (Bouches-du-Rhône).
Euralpin Lyon-Turin Tunnel (ELTT)Auvergne Rhône-Alpes
Euralpin Lyon-Turin Tunnel (ELTT)
ELTT entrusted Eiffage Génie Civil in consortium with the Saint-Martin-La-Porte exploratory structure works.
This is an important stage for the cross-border section of over 57 km on the future Lyon-Turin railway line between Saint-Jean-de-Maurienne in Savoie and Susa/Bussoleno in Piedmont. Saint-Martin-La-Porte descent is the first structure starting from the west. This gallery provides access to the future tunnel level 80 km below. At the foot of the descent, the works involve building a 9 km exploratory gallery, excavated by TBM, in the direction of Italy.
TBM Federica was built to excavate Saint-Martin-La-Porte exploratory gallery. Its dimensions are impressive : 138 m long, 11 m in diameter and weighing 2,340 tonnes. It has the power of 7 Formula One engines.
Perthus TunnelFrance - Spain
Perthus Tunnel has linked France to Spain since February 2009.
Built as part of a design and build contract, this twin-tube tunnel on Perpignan–Figueras HSL was bored by two double-shield TBM named Mistral and Tramontane (inside diameter 8.70 m; excavated section 9.96 m) and covered with prefabricated lining segments.
The structure is 8,300 m long, drilled in rocky ground (granite, gneiss, shale) and boasts 41 safety branches placed at 200 m intervals between its twin tubes, and 4 service passages. A 600 m tunnel access window and an 800 m exploratory gallery were also included in the works entrusted to Eiffage Génie Civil, together with internal structures, track laying, catenaries and all the project equipment.
Line 12Paris region
Paris metro Line 12 has been extended to Aubervilliers by means of a 3.6 km circular tunnel bored under a low cover depth of 16 m. Inside diameter is 8 m, excavated section 66 m2 and excavated diameter 9.15 m.
The tunnel was excavated by earth pressure balance TBM in good holding ground (limestone in Saint-Ouen and sand in Beauchamp) and covered with prefabricated lining segments. The contract also provided for a tunnel vault with an opening of 7.30 m over 32 m, the entry shaft, Front-Populaire Station, two ventilation systems, a dewatering and pumping station, a firefighter access and reshaping work on the existing tunnel terminus.
Violay TunnelAuvergne Rhône-Alpes
This twin-tube motorway tunnel on the A89 between Balbigny and the Tour-de-Salvagny facilitates motorway passage between the Loire and Rhône departments.
It comprises two 3,900 m tubes, bored simultaneously and at each end on four attacking fronts using traditional blasting techniques and the MORSE system (Emulsion Repumping and Sensitization Module).
The works also included 7 pedestrian bypasses, 6 service vehicle bypasses, two 50 m garages, a car-park, an undergound power station with two machine rooms, 52 safety recesses, 50 fire recesses and a retention pond.
Prado Sud TunnelProvence, Alpes, Côte d’Azur
Prado Sud Tunnel
This 1,500 m road structure on two levels - one for each traffic direction (two lanes per direction) – in the centre of Marseille was opened to traffic in November 2013.
A third of the structure was dug under a cover slab built after a first phase of earthworks (known as “mole-digging”) to limit noise pollution and dust for local residents and retailers. This small-sized tunnel (3.20 m high) was constructed using cut and cover techniques, with the help of diaphragm walls, respecting the existing lanes’ right of way.
Maurice-Lemaire TunnelEastern France
For safety standard compliance work on this tunnel built in 1937, a 6,500 m gallery with inside diameter of 5.20 m was constructed parallel to the existing tunnel, which was redeveloped. The gallery ensures sanitary ventilation and smoke extraction (upper part) and enables access for the emergency services and user evacuation in the event of fire.
The works were carried out by open-type TBM of the hard rock kind (excavated diameter 6 m). The existing tunnel was renovated, with the upgrading of the tunnel safety engineering structures and operating and safety equipment, and the extension of this equipment.
The existing tunnel’s concrete ventilation shafts were removed and crushed to supply the gallery’s cast concrete aggregates.
Hydropower development in Pont-Ventoux–Suze (Piedmont) near the French border was carried out as a design and build turnkey project for the Turin Metropolitan Energy Agency.
The tunnels were blasted (30 %) and bored with a 4.75 m-diameter TBM (50 %) and excavator (20 %). This equipment replaces two facilities built in 1910 and 1923. It will ensure annual savings of 86,000 toe (tonnes of oil equivalent) and reduce CO2 emissions by 258,000 tonnes per year.
Lyon-Turin SMP4 Tunnel - 7 years of work in retrospect
Relive with our teams the major stages of this work!