Diabolo Project, Brussels – Railway Technology

This article examines the Diabolo Project, a significant railway infrastructure development aimed at improving connectivity to Brussels Airport (BRU). The project’s primary objective is to integrate the airport seamlessly into the Belgian national rail network, thereby increasing the proportion of passengers and employees using public transport. Currently, despite a gradual rise in rail passenger numbers, road transport remains dominant due to the convenient proximity of the airport to the national motorway network. The Diabolo Project seeks to address this imbalance by enhancing rail accessibility, promoting sustainable transport, and bolstering Brussels’ position as a major European aviation hub. This analysis delves into the project’s infrastructure improvements, rolling stock considerations, signaling and communication systems, and its potential future integration with other railway initiatives. The ultimate aim is to assess the project’s effectiveness in achieving its ambitious targets and its broader implications for Belgian railway infrastructure and sustainable transportation.

Infrastructure Enhancements

The Diabolo Project’s infrastructure component is multifaceted, focusing on improving rail access to and from Brussels Airport. Key elements include the completion of a four-track alignment of Line 36 (Brussels-Leuven/Liège) and the Nossegem Curve, facilitating smoother train movements. The existing three-platform airport station is being expanded to handle longer trains. A crucial addition is a new 3km rail link, incorporating a 300m crossover chamber and two 7.3m-diameter bored tunnels, passing beneath a runway and the Brucargo freight zone. This new link employs unballasted track (UBT) for reduced maintenance and improved ride quality, culminating in grade-separated junctions. Furthermore, the 35km Line 25N, designed for 220km/h (137mph) operation, will connect Schaerbeek in northern Brussels to Zemst, rejoining the existing line south of Mechelen. This new line cleverly utilizes a 40m-wide central reservation within the existing E19 motorway, minimizing land acquisition and environmental impact. A separate project aims to alleviate the bottleneck at Mechelen station through a new line and station to the east of the city. This comprehensive infrastructure upgrade is designed to significantly increase capacity and reduce travel times.

Financing and Project Management

The Diabolo Project employs a Public-Private Partnership (PPP) model. Infrabel (the SNCB Group infrastructure body) is funding Line 25N, while Northern Diabolo NV, a PPP entity involving Babcock & Brown and HSH Nordbank, is responsible for financing and constructing the airport section. The tunnel construction contract was awarded to the consortium THV Dialink. Revenue generation for the private sector partners is diverse; it includes fixed fees, a levy on airport rail tickets (excluding staff), and contributions from domestic rail service operators. The ownership of the airport section will transfer to Infrabel in 2047, completing the transition to public ownership.

Rolling Stock and Operational Considerations

The new lines are designed to accommodate SNCB/NMBS (Belgian National Railway) rolling stock, encompassing multiple units, hauled trains, and push-pull formations. The infrastructure’s capacity allows for future integration with international high-speed services like Thalys (Amsterdam-Brussels-Paris) and NS Hispeed trains, although this hasn’t been formally announced. The existing fleet will be utilized with any potential upgrades determined based on future network demands and operational needs. This approach reduces the financial burden of purchasing new rolling stock while preserving flexibility for future expansions.

Signaling and Communication Systems

The signaling system for the new lines will be compatible with the main Belgian network and designed to support both high-speed international and domestic services. The implementation of Train Borne Line 1 plus (TBL1+) and European Train Control System Level 1 (ETCS Level 1) ensures interoperability and enhanced safety features. This standardisation reduces the need for specialized signaling equipment and facilitates seamless integration with existing systems, reducing operational complexities and costs.

Conclusions

The Diabolo Project represents a significant investment in Belgian railway infrastructure, aiming to fundamentally alter the accessibility of Brussels Airport. The project’s success hinges on its ability to shift a considerable portion of airport-related travel from road to rail, alleviating congestion and promoting sustainability. The integration of a PPP model demonstrates an innovative approach to funding large-scale infrastructure projects. While the completion of the project in 2011 and the commencement of services in 2012 mark a significant milestone, ongoing monitoring and evaluation of its impact on passenger numbers and traffic flow are essential. The project’s long-term success will depend on several factors, including effective marketing and communication to encourage rail usage among travelers, seamless integration with other transportation modes, and the ongoing maintenance of the upgraded infrastructure. Future integration with the Brussels RER (regional express rail network) further enhances its potential to become a truly integrated part of the broader transportation system. The combination of upgraded infrastructure, modern signaling systems, and flexible rolling stock options presents a blueprint for other large-scale railway projects aimed at integrating airports into wider public transportation networks. The ultimate goal of increasing rail usage to 40% of airport journeys by 2015 remains a significant challenge, requiring sustained efforts in promotion and operational optimization. The project’s impact on Brussels’ status as a major European hub will be a key indicator of its long-term success.

Company Information:

• SNCB/NMBS: Belgian National Railway Company.
• Infrabel: SNCB Group’s infrastructure manager.
• Northern Diabolo NV: Public-Private Partnership (PPP) entity. Involved Babcock & Brown and HSH Nordbank.
• THV Dialink: Consortium awarded the tunnel construction contract.
• Babcock & Brown: (Information not available in provided text)
• HSH Nordbank: (Information not available in provided text)
• Siemens: (Mentioned as supplier of rolling stock for RER project.)