The Netherlands about to join the High-Speed Rail Club in Grand Style!
The Netherlands is not the easiest place in which to build a new high-speed railway, but HSL-Zuid is nearly complete and has been built with style as well as engineering expertise. As you approach the new railway it is difficult not to be impressed by the distinctive, architect inspired, and unique design of the overhead line masts.
The HSL-Zuid Project will provide the Dutch with a 300-kph railway from Amsterdam southwards to the Belgian border, a distance of some 100km. Journey times between Amsterdam and Paris or Brussels will be reduced by over an hour, and in some places internal domestic travel times will be halved - i.e. Amsterdam to Breda, or Rotterdam.
Availability and User Fees
The total cost is around 6.7 billion euros, but the building of the substructure and railway infrastructure it carries, are being met by a public private partnership arrangement requiring no initial government investment. The contracts cover both construction and 30 years maintenance. Following completion, the Netherlands government will pay around 106 million euros (excluding VAT) each year as an ‘availability fee’ but they will offset this with the 148 million euros they expect to receive each year from the train operator as ‘user fees’.
The government let contracts to cover design, construction and operation. The initial five-year period 2001-6 was for building, followed by operation until 2031. The issuing of a Certificate of Availability (COA) will trigger agreement for the commissioning of the new railway. After the initial 25 years of operation, ownership of the railway, and responsibility for its operation, will pass to the state.
Although the Netherlands government is contractually committed to pay about 290,000 euros each day during the operation phase of the contract, availability of less than 99.46% would result in no payment being made at all! This ensures a huge incentive for high reliability and availability, but the train operation licence payments are equally important, since they are planned to more than cover payment of full availability fees.
How it all began
Initial plans from the 1970s were brought together with an agreement in 1989 between France, Germany, Belgium and the Netherlands, which led to the production of an agreed memo in 1994 setting out the plan. In 1998 the decision was finally made to build the railway. In 2000 construction contracts were signed with six consortia of mainly Dutch contractors for the design and building of the substructure.
Specialists from other European countries also became involved. The substructure specification calls for a 100 year design life, and parts of it are built on reclaimed land beneath sea level, protected by dikes. Throwaway comments from local engineers about depths below sea level tend, at least initially, to disrupt the thinking of those more used to mountains!
Three tunnels, and a large bridge
Major tunnelling challenges faced the substructure consortia. A bored tunnel has been built beneath the Green Heart Pasture Reserve (Groene Hart). It runs between Benthuizen and Hoogmade, a distance of some seven kilometres. Using a boring machine, which averaged around 15 metres each day, the work took two years and two months. The tunnel has an internal diameter of 13.3 metres and is lined with over 35,000 pre-cast concrete segments.
There are also two, almost identical, submerged tube tunnels at Dordtsche Kil and Oude Maas. Both have one tube per track, each measuring 7.35 by 7.0m. Inclusive of ramps at both ends, each of the four tubes are around 2,500m long, and took four years to build.
The bridge over Hollandsch Diep is a large steel structure, covered with a concrete top layer. It runs alongside an existing rail bridge, and is some two km long, with 1.2km over water. It took just three years to build.
Substructure design criteria
The majority of substructure designs were divided into three distinct categories based on their permitted design criteria. From Amsterdam’s Schipol Airport southwards to Rotterdam, category 1 structures were stipulated. For these, support structure piles have been used to penetrate through the five metre deep layer of peat into the sand layer beneath.
Category 1 criteria permit maximum settlement of 30mm, differential of just two mm and gradients of 1 in 2,000. These structures are described as ‘settlement free’. In the piled areas, a combination of short viaduct spans, one per track, and ‘settlement free plates’ have been used.
For the bridge Hollandsch Diep and the immersed tube tunnels between Rotterdam and Breda, category 3 is specified. These areas are described as ‘settlement sensitive’, needing special structures. In this area the peat layer is up to 20m thick, with a maximum settlement of 50mm, differential 2mm, but a gradient of 1 in 350.
To the south of the Breda connection the sand layer comes to the ground surface and substructures are described as category 2. Embankments rather than support structures have been used with settlement of up to 30mm, and a gradient requirement of no more than 1 in 500.
Funding, interest payments and dividends
Funding and commercial arrangements for the construction and twenty-five year maintenance of the railway superstructure is rather different. Infraspeed BV was set up for this purpose. Its shareholders are Fluor - the project management company, Siemens, who are responsible for the signalling and electrification work, and BAM the track work, buildings and noise control contractors.
Apart from their own capital investment in the project, a financing consortium of about 24 banks has provided credit funding. The six major financial institutions who comprise this are ING, Rabobank, KBC, KfW, Dexia and Hypovereinsbank. Once the trains start to run, they can expect interest return payments on their investment from the State, with the contractor shareholders of Infraspeed BV also benefiting from dividends based on their investment.
Signalling, electrification and (slab) track
Superstructure work began in April 2004 and will be completed early in 2006. Under Infraspeed BV there is a maintenance company and the EPC consortium. The latter has three parts. Programme managers Fluor have an 11% interest, Siemens 46% and BAM 43%. The programme management task also includes coordination with the state, banks, and existing national railway.
Siemens’ work includes power distribution as well as overhead structures and electronic signalling and control systems. BAM’s task, in addition to the track, includes buildings (including transformer houses), fences, balustrades and sound barriers. In addition to BAM’s rail and civil engineering work, Pfleiderer Track Systems BV are the owners of the joint venture Rheda 2000 VOF building the slab track system, which is being used for most of the track.
160 km of Rheda 2000 slab track with Vossloh fastenings
In total 200 single line km of track is being laid. Just 40km of it is ballasted, with the remainder all Rheda 2000 patented slab track, incorporating the Vossloh 300-1 fastening system and DFF 300-1 fastening system for special areas. Generally the fastening system is installed with stiffness of 22,5 kN/mm with low dynamic stiffening.
With a contracted 25 year maintenance period this system has been chosen, despite its higher installation costs, as a way of reducing total cost and minimising future maintenance costs. 86km of single line slab track lies in the northern section and 77km in the south. There are only nine km of single line 300kph ballasted track, the other lines run at 160kph or less.
Switches and crossings on slab track
Switches and crossings look awe inspiring when they are very long, with swing noses supported on slab track. These swing nosed crossings and switches are designed generally for 140kph crossing. There are 15 with 1 in 34 angle crossings and a single one with a 1 in 39 angle, plus two low speed 1 in 12’s into maintenance sidings. There are eight switches on ballasted track, four of them with a 1 in 34 angle, and four with a 1 in 15 angle.
Rheda 2000 Slab Track
For the superstructure works, including the plain line track, the performance of the substructure design is guaranteed to Infraspeed. With the high-speed railway being carried on piles, the superstructure is effectively a long bridge. Consequently it was important to optimise the dynamic behaviour of the track relative to the effectively fixed substructure. The usual Rheda 2000 slab track was therefore adapted by dividing it into lengths of short (6.4m) segmented slabs to match each settlement free plate beneath. The more usual design is for a continuous slab.
A grid of steel dowels
Originally most slab track was designed as a trough with the sidewalls or upstands carrying the high transverse forces. Later designs relied on a central ridge to do the same job, otherwise described as corbels. In the Netherlands the contract and funding programme led to the situation where a 700mm substructure slab was already built, leaving just 240mm available for slab construction - not enough for a corbel! The solution eventually adopted was to design and install a grid of steel dowels capable of carrying/transmitting the high transverse dynamic loads, whilst allowing for longitudinal expansion movement at the same time.
Hilti’s research in Liechtenstein
At Christmas 2003, in Hilti’s Research Centre in Liechtenstein, a test rig was running to apply shear forces of max 140 KN (design value max 33 KN) together with tensile stresses ten million times to prototype dowels. By the summer of that year a design had been proven which would ensure adequate shear connection between the slab and its foundation.
The dowel system consists of nine 40mm diameter by 180mm long stainless steel dowels set to a grid, in the middle of each of the 6.4m slabs carrying the rails and fastenings plus two more at each end. The dowels are made from steel with a higher strength than A4 stainless, but their detailed properties have not been revealed. A geotextile layer is installed to overcome the friction between the relatively coarse finish of the substructure (measured coefficient of friction 0.4, design assumption 0.1) and the Rheda 2000 slab track. Plastic wrapping and debonding collars round the dowels, completes the de-bonding between the substructure and the slab track.
Stainless steel dowels into slotted holes
Expansion with temperature of the slabs is allowed for by a 100mm gap between each. The dowels at both ends of the slabs have been designed to allow for longitudinal expansion and slot into preformed elongated sheaths with a polystyrene lining.
The Hilti engineer’s design is a round bar with the upper part having two parallel flat surfaces so that it looks as if it has been squashed from both sides. The lateral forces from the dynamic loading are carried by these surfaces. Hilti also specified the use of rectangular stainless steel guides, which are placed over the connecting dowels.
750 dowels and 300 metres each day
The two dowel types are HCD-O for the ends and HSD-C for the slab central areas, set in HIT-RE 500 adhesive mortar, a two part epoxy which needs a minimum temperature of five degrees celsius, hence the provision of the rail mounted tent. A Hilti ferroscan detector is used to locate the exact position of the substructure reinforcement so that the 44mm diameter holes drilled for the dowels are kept clear.
About 750 dowels are being set each day, which means that the drillers are able to keep pace with the construction team’s slab output of 300m each day. Around 500m a day could be achieved, but the lesser target ensures time for the necessary accuracy to be reached.
In the centre, the dowels have plastic caps to hold the O-rings in place. The cap prevents the dowels from punching through the concrete surface. Innovative engineering, but with a design life of 30 years for the superstructure, the contracted maintenance teams should never need to be involved.
The French Fassetta machine was developed specially for the first stage alignment of the service railed track before concreting. Its four frames take a section of track, between 12 and 50 14.5m lengths long, and by reference to the intermediate targets using a site lap top computer with Intermeric software from a Stuttgart company, roughly correct the track position to within plus or minus 5mm!
Also before concreting, earthing connections are flash butt welded in place. Once the accurate final alignment adjustments have been made, and planned settlements of 0.3mm brought in during concreting, the slab can be poured.
Concrete in the Netherlands is different
The slab concreting part of this essentially production line process can use any form of concrete delivery. Although Pfleiderer and Rheda 2000 are German systems, their people in the Netherlands have come to terms with using very different concrete mixes, some aspects of which would not be permitted back in Germany.
Ordinary Portland cement with a 0.5 water cement ratio plus both a plasticiser and retarder are required to meet Netherlands regulations and practice. Before concreteing, the ratchet bolts supporting the track are torque adjusted and a check reading is taken on every third sleeper. Accuracy to one tenth of a millimetre is the result, and a very sensible target for those with 25 years’ future maintenance in their contracts! It is estimated that a million trains each with 52 axles exerting dynamic loads as they pass at up to 300km an hour will use the railway before it passes into state ownership.
Heated to the stress free temperature
The final construction tasks are to remove the service rails and replace them with 120m long ones, which are then welded into continuous rails. The long 120m lengths are brought on site and offloaded from purpose made rail mounted trailers. A track-mounted machine is then used to heat the long rails to achieve the necessary stress free temperature before they are finally welded up, again from a specialised rail mounted trolley.
Scott Wilson Rail again!
The route between Rotterdam and the Belgian border is due for completion in April with the northern leg from Amsterdam following six months later. A period of testing and test running will follow and the running of scheduled services is due to start within a year of completion. Visiting the site, Colin Wheeler expected to learn of mainland high-speed railway expertise in both design and construction. You can imagine his surprise when he discovered the involvement of Scott Wilson Rail, and Roger Bastin, in looking after the interests of the scheme’s funders!
Britain lagging behind on high-speed rail
Here in Britain we are lagging behind. Railway engineers know that rail is better than air when carbon emissions and global warming are considered. Yet we lag behind mainland Europe in building dedicated high-speed railways.
The long awaited Channel Tunnel Rail Link is our first and only high-speed railway. Chris Green, speaking in Milan and elsewhere, has called for a purpose built high-speed London to Scotland route. GNER’s near 9% hike in East Coast passenger fares is just one small indicator of the market for travel from north to south.
In December the Institution of Civil Engineers launched a report entitled ‘The Missing Link’, which recommends the building of a high-speed route to reduce travelling time between Scotland and London to less than three hours. Could this be the opportunity for us to take on board, and use the lessons learnt and expertise developed, in both funding and building the high-speed railway of the Netherlands HSL-Zuid? Why not an HSL-Zuid running at 210mph between London and Scotland, using Rheda track slabs and Vossloh fastenings - or has anyone got a better and proven solution?
HSL Zuid - Scott Wilson’s Role
This project is unique as the substructure for the railway, which includes all bridges, earthworks and tunnels, is provided by the Dutch State; everything on top of this is contained within a PPP. Scott Wilson and the project team are very proud to be working on Europe’s largest rail PPP project, and the project won the ‘European PPP Project of the Year’ award in 2001.
Scott Wilson’s involvement on the project can be traced back to the year 2000. Our services are two fold: technical due diligence advice to the lending banks during the period up to financial close, and monitoring and certification work during the whole 30 year concession period for this finance, design, build, operation and maintenance contract.
Technical due diligence
Scott Wilson was retained by one of the bidding consortia, Infraspeed (a consortium of Fluor Daniel, Siemens Transportation Systems and Civil Engineering contractor BAM NBM) during the BAFO (Best and Final Offer) period, to undertake technical due diligence works on behalf of the lending banks. Infraspeed was successful and was awarded the 25+5 year concession to design and build the railway systems (track, electrification and signals) and to maintain the whole of the infrastructure, including the civils substructure, of the 95km, high-speed railway between Amsterdam and the Belgian border.
Scott Wilson’s involvement at the due diligence stage included the following:
Monitoring and certification
Following the financial close in 2001, Scott Wilson was appointed by Infraspeed and the lenders as Technical Advisors (TA) to provide the lenders with monitoring and certification for the 25+5-year concession period. Our involvement during this stage includes:
Scott Wilson has assembled an integrated team for this project by drawing the best resources available across Scott Wilson from various disciplines, headed by Keith Wallace, CEO of Scott Wilson Railways. The assignment is currently being jointly managed and undertaken by Scott Wilson Railways (SWR) and the commercial team of Scott Wilson Business Consultancy (SWBC). We work coherently and supportively on both technical and commercial issues through a combined team of highly experienced technical, financial and commercial specialists, as well as an efficient assignment management team.
Throughout the due diligence and monitoring periods, the project team has experienced many challenges in technical, environmental, contractual and commercial aspects.
Complex interface issues
In the technical area, some 170 structures including tunnels, flyovers, aqueducts, underbridges and overbridges have been built by civil contractors under separate independent contracts. For 7km, the line was built in a single bore tunnel of 15m diameter (the world’s largest diameter tunnel at the time) at 30m below sea level at the Groene Hart, a region of open country, in order to protect unspoilt nature and wildlife. The separation of civil works and railway systems has led to a number of complex interface issues that Infraspeed has had to deal with and which the TA team has had to understand and review on behalf of the lenders.
In addition, significant changes in construction details of the German Rheda 2000 non-ballasted track during the design period have led to several concerns on the part of the TA team and the lenders. These changes have been reviewed in detail by Roger Bastin (track specialist), and have been the subject of many exchanges with the lenders.
In the commercial area, we maintain close contacts with the lending banks and the consortium to ensure the project risks are minimised or mitigated from both the banks’ and consortium’s interests through a proper risk management approach.