Currently the biggest infrastructure project in Belgium, The Liefkenshoek Rail Tunnel project involves the construction and maintenance of the civil infrastructure for a new 16.2 km freight-only railway in the bounds of the Port of Antwerp undercrossing the River Schelde and the Canal Dock.
In 2013 the new tunnel will connect the left bank of the River Schelde with the right, linking the western and eastern docks of the city.
The project, valued at 680 million Euros, is intended to provide a solution for the large rise in goods transport by rail which is expected in the area.
The scheme is a design, build, finance and maintain agreement, with a maturity period of 41½ years (3½ years for construction up to availability, plus 38 years after the achievement of availability for maintenance).
The project involves the construction and maintenance of civil infrastructure (with associated electro-mechanical systems where essential for maintenance of the civil infrastructure) to provide for others to construct, maintain and operate the railway.
The project is being carried out for Infrabel N.V. Following several tendering phases the contract was awarded to the successful bidding consortium LocoRail NV in November 2008.
This consists of the Belgium company CFE NV, the French VINCI Concession SA company and the Dutch company BAM PPP. Mott MacDonald Ltd will be Technical Advisors to the Locorail consortium’s lending bank.
The project comprises a double-track route from Bundel Zuid to the Antwerp North marshalling yard, which runs under three water bodies: the Waasland canal (through the already existing but never used Beverentunnel), the River Schelde and the Kanaal dock. The rail link consists of 4.8km of embankment, 4.2km of open and covered trench, 1.2km of existing tunnel (re-opening of the already built but never used Beveren Tunnel) and almost 6km of double-bored tunnel with an internal diameter of 7.3m.
The two single-track tunnels roughly 5,970m long are being created by shield driving and an internal diameter of 7.3m, as well as several km of tunnels by cut-and-cover with deep diaphragm walls and cement-bentonite.
The tunnel boring machines (TBMs) made by Herrenknecht, are approximately 8.4m in diameter and have a conic tail skin. The tunnelling installation including five trailers, is about 110m long. Both TBMs are fitted with an electric drive with an installed thrusting force of roughly 60,000kN and the operating pressure of the TBMs amounts to 4bar. The TBMs are equipped with a closed cutting wheel, which rotates in front of the shield.
Wiske is the name of the tunnel boring machine (TBM) that, on 26 March 2010, began digging a tunnel shaft from the departure shaft on the Ploegweg on the Left bank in the direction of the reception shaft on the Kruisweg.
The first boring shield, Schanulleke, began boring the other tunnel shaft on 8 February 2010. Both boring tasks are running simultaneously so that the new rail link can be realised according to the planned timeframe. Work generally takes place continuously: 24 hours a day, 7 days a week in shifts.
At the end of July 2011, Schanulleke (which has currently bored 4.5 km) will reach its end point on the Right Bank. This tunnel shaft will be the base for a number of additional tasks such as the construction of the evacuation shafts, the tunnel connection and a platform to facilitate the passage of the work trains (the ‘Menriders’). Both tunnel borings run parallel and follow the same path.
The two boring shields dig about 15 metres every day (the TBM also installs 1.8 m wide tunnel rings one after the other) and a top speed of 45 metres per day was recorded on 19 April 2011.
Both tunnels are bored separately using a 102 m long boring machine on steel rollers, proceeding with assistance from a high-pressurised water hydromix shield. The complete boring task is computer and laser driven and takes place under the supervision of TUC RAIL, Infrabel’s rail technology consultancy.
A crucial phase during the task was boring to +/- 40 metres under ground level (ground floor) of the Scheldt and +/- 30 metres under the ground level of channel dock B1-B2. This was prepared in minute detail and executed by TUC RAIL and the building consortium THV LOCOBOUW so that shipping would not be inconvenienced.
In preparation for this, THV LOCOBOUW deposited approximately 30,000 m³ of concrete in the channel dock last year and then installed a 2 metre thick concrete plate on top. This spectacular underwater operation took place from floating pontoons using divers. The aim was to realise an improvement to the base in order to guarantee the safety of the excavation works for the tunnel under the channel dock.
Along the tunnels there are 13 cross-passages and eight connections with evacuation shafts. Generally speaking the cross-passages and evacuation shafts are built alternately at approximately 300m gaps. Beneath the River Schelde five cross-passages at gaps of roughly 250m without any evacuation shafts located between them are being created.
The new link will enable trains to travel back and forth without having to leave the port area. In addition operating costs for the trains will be lower as the railway route between the larger locations on both banks will be reduced by roughly 22 km.
Safety is an absolute priority. For instance, electromechanical installations are provided in the tunnels (smoke, heat and water vents), and access roads and shafts to the tunnels are being built for emergency services. A fire fighting system has also been installed.
When it comes to safety, the emergency services will be provided with access passages and shafts to the tunnels, there will also be 600 metres of evacuation shafts (14 in total) and cross passages (13 in total) at every 300 metres. The rail tunnel will be equipped with safeguards such as a fire detection system (including cameras), an evacuation system (including smoke and heat removal systems), an automatic foam extinguisher system and fire-resistant concrete. The Liefkenshoek rail link will also be fitted with the European train control system (ETCS).
Infrabel is integrating the rail infrastructure in the environment in a sustainable manner via the realisation of a 54 hectare natural compensation area (The Groot Rietveld in Kallo) which has already been completed. A range of sound buffers will also be installed in Kallo and several sound screens will be constructed in the surrounding area. During tunnel boring, Infrabel will also use a special 7,000 m² purification installation in Kallo that separates soil and bentonite (a mixture of water and clay that is used during building work).
In total, the project involves the use of 400,000 cubic metres of in situ concrete and 40,000 tonnes of reinforced steelwork.
By mid 2013, the building works will have been completed. In the period 2012-2014 Infrabel will execute the works on tracks, signalling infrastructure and overhead wiring in several stages. Infrabel will integrate the new rail infrastructure into the surroundings in a sustainable way by building a compensation area at Groot Rietveld in Kallo, three noise buffers around Kallo, Verrebroek and Zuidelijke Groenzone and noise screens.
From the spring of 2014 onwards the rail infrastructure of the Liefkenshoek rail connection will be tested.
On account of the intensive use of the Port of Antwerp, especially on the left bank of the River Schelde where 7.5m containers are handled each year, a considerable increase in goods transportation by train is anticipated.
Smet Aannemingen is responsible for the transportation of all the excavated materials by TBM North and South on the project. Three products are derived after washing and percolation; sand, clay and bentonite.
All products are re-used in other projects. Smet Aannemingen started in February 2010, and since then are we responsible for a continuous transport for all materials, twenty four hours per day, seven days a week. A well organized transportation network is important for the continuous flow of both TBM’s.
The sand is re-used in the elevation of a logistics park of sixty hectares, using track loaders and ground dumpers. Bentonite and clay are used in the construction of a sound barrier.
The machines used for transport have to perform well under all weather conditions (wet autumn-cold winter-dry summer) and they need to work well 24/24- 7-7.
The transport is done by 15m³ ground dumpers. These are qualified to perform well on public roads as on difficult accessible roads. With an average of 5 tractors each day working 24 hours per day, 7 days in a week, the company is capable of providing a well considered logistic solutions to dips and peaks in the supply of materials.
During the planning phase the road tunnel below the Schelde – an immersed tunnel – had to be taken into consideration. It was built in the 1980s and is located close to the new tunnel route. Furthermore restrictions relating to gradients for railway tracks had to be observed, which are considerably flatter than those for roads.
The geology along the route consists of fill, quaternary sands (alluvium), several layers of tertiary sand with various formations (Kattendijk, Merksem, Berchem, Lilo, Kruisschans) with low proportions of clay and glauconite as well as Boomse Klei, a stiff, overconsolidated and fissured tertiary clay, which is located underneath in the form of a sealing layer.
By and large the tunnel route is located in tertiary sands; however, the clay only ranges upwards to a maximum of 40% of the tunnel cross-section.
Special attention has been accorded the riverbed of the Schelde with its silt deposits and thick layers of faulty sedimentary soil as well as the Canal Dock, where silt deposits also have to be given consideration. In the Canal Dock the silt is to be replaced by sand at the behest of the client.
In the course of the project a free groundwater level above the so-called “Polderkies” (clay) in the quaternary sands and 2 artesian groundwater levels above the Boomse Klei have to be taken into account, split up by Kruisschans sands, which are interstratified by clay lentils.
Furthermore the water levels along the banks of the Schelde are greatly dependent on the Schelde’s tides at the land side, which fluctuate.
Infrabel will carry out works on tracks, signalling infrastructure and the catenary system between 2012 and 2014. In spring 2014, the rail infrastructure of Liefkenshoek rail link will be tested. After the required approvals, Infrabel will make this new rail link available to the railway operators in mid–2014.
The Liefkenshoek rail link fits into Infrabel’s strategy for a step-by-step capacity expansion of the rail infrastructure and an improvement of the traffic flows between the strategic Deurganckdok (the Waaslandhaven) and the marshalling yard Antwerpen-Noord on the Right Bank.
The Liefkenshoek rail link means that trains will no longer have to make a detour around the junctions (Kennedy rail tunnel and the rail axis Antwerpen-Berchem – Antwerpen-Schijnpoort) and this will, in turn, free up capacity on the surrounding lines for passenger travel.
With this rail link, Infrabel aims to provide progressive support to the growth of the port of Antwerp within the context of optimum intermodality between rail and water.
Even during the crisis, Infrabel has been proactive in terms of ongoing investments in rail infrastructure, to the benefit of its customers, in preparation for the current increase in freight transport. Infrabel would like to expand the share of rail traffic in the port of Antwerp from the current 10% to approximately 15% by 2020.
Infrabel is the public limited company responsible for the management, maintenance, renewal and development of the Belgian railway network.
The company is also responsible for the allocation of train paths to all Belgian and foreign operators. Infrabel’s specific shareholders structure guarantees complete independence.
The firm was established on 1 January 2005 following the split of the Belgian railways and is part of the SNCB Group. Today, the company employs some 12,500 people and generates revenues of approximately 1 billion
Infrabel is a part of the SNCB group, with a stable financial basis. Headed by Infrabel’s CEO, Luc Lallemand, the company has three directorates, six general departments and an internal audit department.
The directorates consist of the Infrastructure Directorate which renovates and maintains the existing rail infrastructure; the Network Directorate organises and monitors the train traffic in real time, and the Rail Access Directorate allocates the railway network to different operators and invoices its use.