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In a EUR 162 million project, two parallel tunnels were excavated to provide a path for a new high speed railway in Spain. SGS provided technical assistance and inspection services between Pajares and Sotiello, part of the future León-Asturias railway line.

The new high speed line, which will connect the Léon and Asturias stations, will replace a line that is 120 years old. Trains running on the old line move very slowly, as they must traverse 79 tunnels and navigate high slopes and ramps. Replacing the old line with an efficient high speed railway will benefit people and businesses in the region.

Improving the Infrastructure

The new tunnels will help trains to move quickly from station to station. Each tunnel is about 6 kilometers long, with an internal radius of 4.43 meters.

To ensure the safety of the project and the quality of the work, Spain’s Railway Infrastructure Administrator (ADIF) hired SGS, in a joint venture with the engineering consulting firm INOCSA – later acquired by AECOM – to help with the excavation of the tunnels.

ADIF had worked with SGS many times in the past and knew that SGS excelled in the provision of services for railways.

Ensuring Quality Work and Compliance with Standards

SGS was awarded the EUR 1.6 million contract in January 2007 and began work in April of that year. SGS lent its expertise to the project by:

  • Coordinating the activities of the companies involved with planning
  • Monitoring construction
  • Inspecting the works to ensure compliance with regulations
  • Performing health and safety inspections
  • Preparing reports and controlling documentation

In addition to assisting with the tunnel excavation, SGS helped with the construction of:

  • Two galleries, 21 and 41 meters long, connecting the tunnels
  • Two 124-meter long viaducts
  • Workshops and other facilities
  • Access roads
  • Landfills

SGS also played a role in the replacement of a road in the south tunnel and in the replacement of affected electrical, lighting and telephone services.

An SGS team, which included experts in civil engineering, geology and topography, helped in the field, while additional SGS experts worked in the lab.

Over the course of the project, SGS introduced many technological improvements. ADIF expressed its satisfaction with SGS’s work by extending the contract term from 39 to 64 months.

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