Railway Signaling Modernization - SNCF Lyon Hub

SNCF Réseau is the French national railway infrastructure manager, responsible for maintaining and developing over 28,000 km of railway lines across France. The Lyon rail hub is one of France's most critical junction points, connecting high-speed TGV lines from Paris, Marseille, and Geneva with regional and freight networks. Over 1,200 trains pass through the Lyon hub daily, making it the second busiest rail node in France.

SPIE delivered a full signaling modernization programme for the Lyon Part-Dieu and Lyon Perrache rail hub, one of the most complex and heavily trafficked junctions in the French rail network. The project replaced legacy relay-based interlocking systems with modern computer-based interlocking (CBI) technology, installed new generation track circuits and axle counters, and deployed a high-capacity fiber optic communication backbone linking all signaling nodes. Integration with the existing ERTMS Level 2 overlay on the LGV Sud-Est high-speed line required meticulous interface management and rigorous safety case development. All installation and commissioning work was conducted during scheduled possession windows, typically between midnight and 5 AM, to preserve the hub's daily capacity of over 1,200 train movements. The modernized signaling infrastructure supports a 20% increase in line capacity, directly enabling SNCF Réseau's growth targets for the Lyon metropolitan area.

• 20% increase in line capacity at the Lyon hub through modern signaling technology
• Zero unplanned service disruptions during 18 months of active construction
• Enhanced safety through computer-based interlocking with SIL 4 integrity
• 30-year design life reducing long-term infrastructure maintenance costs

• Computer-based interlocking (CBI) design, installation, and commissioning
• ERTMS Level 2 system integration and interface management
• Fiber optic backbone deployment for railway telecommunications
• Railway safety case development and independent safety assessment coordination