HIGH SPEED RAILWAY OF THE BASQUE COUNTRY. SECTIONS: ANDOAIN-URNIETA-HERNANI

Area of activity
TRANSPORT INFRASTRUCTURES

Service
Railways, subway and LRT

Client
ETS – Euskal Trenbide Sarea

Scope

• Technical assistance to site supervision
• Modified projects development

Duration
2014-2018

The general purpose of this contract is to provide support services for the Management, Control and Supervision of the construction works associated with the New High Speed Railway Network (HST) in the Basque Country, Andoain-Urnieta and Urnieta-Hernani sections, belonging to the Gipuzkoa branch of the New Basque Y Railway Network.

With a global cost of the works of more than 222 million euros, the scope of the works is focused on the advance of the network through the northwest of Gipuzkoa, through the part closest to Donostia-San Sebastián and the border with France, since up to that moment all the cuts were located in Tolosaldea, Goierri and Alto Deba.

The Andoain-Urnieta section, with a total length of 2.8 km, begins with the Viaduct over the Oria River. This important structure crosses over the river and the A-1, and is located 1 km north of the town of Andoain. Its design, adjusted to all the conditioning factors of the area, is projected with a central span of 115 m and a total length of 339 m.

Next, the railway platform passes through the Andoain Tunnel, 1,938 m long. This tunnel has an emergency gallery of almost one km, with its connecting corridors with the main body of the tunnel and its necessary widening to facilitate the crossing of vehicles.

At the exit of the Andoain Tunnel, the future railway axis runs in a 100 m long cut and after which a 200 m long viaduct over the GI-131 road is projected.

The Urnieta-Hernani section, with a length of 5.2 km, presents in its initial part 25 m of open-air section, immediately before the beginning of the Urnieta false tunnel of 498 m in length. This structure precedes the Urnieta tunnel, 2,157 m long. For this tunnel, two emergency galleries are planned for a total length of 1080 m.

After leaving the surface once the tunnel has been passed, the route crosses over the Uban stream with a 163 m long bridge and enters the municipality of Hernani. The route continues with a trench section up to the start of the 185 m long Errotaran cut-and-cover tunnel, which precedes the 801 m long viaduct over the Urumea River. This bridge crosses over the river itself, the Ibarluze industrial estate and the vicinity of the Altzueta cider mills.

The Urumea bridge connects with the 769.789 m long Hernani tunnel, the northern end of which connects with a box structure that allows passage under the Urumea Highway.