INTRO: A demanding schedule has been set for installing track and M&E equipment on the first section of the Channel Tunnel Rail Link. Murray Hughes visited the tracklaying base at Beechbrook Farm near Ashford
VISITORS to Britain arriving by Eurostar consistently express surprise at the slow pace of travel between the Channel Tunnel and London compared with the 300 km/h line speed in France. Not for much longer. Britain’s first dedicated high speed railway is making good progress - and Eurostar passengers can see for themselves the construction sites parallel to the existing line between the Tunnel and Ashford.
The 70 km Section 1 of the 109 km line is set to open in May 2003, cutting 20min off journey times from London to Paris and Brussels. Parts of the formation are already complete and awaiting tracklaying, due to start on November 12.
Once the first track is laid, work will proceed rapidly as the contractors have an access window of just 11 months for use of the worksite at Beechbrook Farm near Ashford. This summer saw the site buzzing with furious activity as the tracklaying and other equipment teams prepared for the day when they begin laying steel.
One small milestone was passed on June 10 when a Class 37 diesel loco propelled a train of 24 tonne ballast wagons into the site. Carrying several hundred tonnes of ballast for the worksite’s own tracks totalling 14·8 km, it gave the staff a foretaste of what is to come. For ballasting will be crucial to the whole process.
Bob Doty, CTRL Contract Manager for Contract 570, says that ’ballast delivery drives everything’. Every morning 6000 tonnes of granite will arrive in four trainloads from the Isle of Grain, where it is stockpiled en route from quarries in Scotland. In case of problems, there will be one week’s additional stockpile at Sevington east of Ashford and two trains with 1500 tonnes of ballast ’on standby’.
Such measures are needed because the tight timescale for tracklaying and installing other equipment leaves no room for delay. ’We have come up with plans to deal with anything we can think of’, says Doty, who believes that records may be set for the speed of work.
Doty, whose railway project management experience dates back to the 1970s, sees the job in terms of minimising risk and balancing this stricture with cost. ’We are trying to minimise risk by sticking with known, but best-case, technology’. But he acknowledges that this is ’inconsistent with engineering - you can sum it up in the saying that better is the evil of good, and I have worked on jobs where they engineered until the paint was dry.’
Doty has no intention of that happening with the CTRL. Next month the Beechbrook Farm site will be in full swing, but given the 11-month deadline there will be no room for mistakes or delays - ’the programmed work must be completed every day as a day lost cannot be recovered’, he says. ’The two primary challenges are that the site is rather small and that it has to be managed on a just-in-time basis; we are not allowed to store materials, and this makes it almost a factory environment.’ When the site is at full throttle with up to 2000 people at work, ’up to 20 different units will be dispatched every morning’.
Doty says that the tracklaying teams ’will use SNCF methodologies’, and indeed contractor AMEC Spie Rail Systems has a number of French staff at Beechbrook Farm, some of whom had worked on TGV Méditerranée. Deputy Construction Manager for Contract 570 David Taylor feels that the combination of British and French expertise ’has worked very well with a genuine meeting of minds’. Bringing the international team together has meant ’taking the blinkers off’ and has included language courses at all levels ’as nothing must be lost in translation - and all this had to be incorporated into the planning.’
The tracklaying and equipment installation process along the alignment begins with cable troughs, cross channels and cable-laying, followed by footings for overhead line equipment. Tracklaying can then begin, followed by erection of masts and 25 kV 50Hz catenary, which is to the standard SNCF design for 300 km/h. Finally, the TVM430 signalling, communications and other M&E equipment will go in, although some communications equipment at sites off the alignment was in fact installed in July.
The first track will be laid from Beechbrook Farm towards Ashford, but this will be just for staff training. The head of steel will proceed first towards Fawkham Junction, and only then will the teams work back from Beechbrook Farm towards the Channel Tunnel.
Doty says that tracklaying must go forward at ’a minimum of 1100m a day’ (550m of double track), with peaks of 1300m expected. The process entails assembly at Beechbrook Farm of temporary panels that are laid out along the alignment to form one track over around 7 km. Sleeper and rail trains then use this to install the permanent track consisting of Stanton Bonna concrete sleepers spaced at 600mm intervals. Long welded UIC60 rail from Thyssen-Krupp (taken over by Voest-Alpine in July) is then installed and affixed with Vossloh fastenings. Final ballasting then takes place.
As many as seven ballasting passes will be needed to achieve the nominal ballast depth of 350mm with six 16 wagon trains a day leaving Beechbrook Farm in the charge of Class 66 locomotives, hire of which Doty was negotiating in July.
Crossovers will be located approximately every 10 km using turnouts from Cogifer; these will permit trains to take the turnout at 170 km/h. Two sets of loops are being laid at Charing Heath and at Singlewell near Gravesend to comply with a contractual requirement for the line to handle freight traffic. Just what form this would take is unclear, as the track design is intended for Eurostar or similar TGV-derived trains with a 17 tonne static axleload.
The Section 1 alignment is designed to permit 300 km/h running throughout, including on the through tracks adjacent to Ashford station, in the 3·2 km North Downs tunnel, and across the 1·25 km Medway Viaduct that is due for completion this month. On Section 2, 230 km/h will be permitted through the Thames tunnel and in the 19 km London approach tunnels. Steepest grade on the line is 2·5%.
Flooding in the winter of 2000-01 had caused some delays to civil engineering work but these have ’almost all been mitigated now, and our programme is starting when it is supposed to start’, says Doty.
There are complex interfaces with Railtrack to manage at Cheriton, Ashford and Fawkham Junction, and Doty says these are being handled as ’separate outstations’ with a manager at each one. ’Regular meetings with all interface parties are held to identify and resolve issues, and progress has been very co-operative and productive’, he explains.
It is clear that success hinges on good management, organisation and logistics. ’We tried to make this as interesting as we could’, quips Doty, ’and it’ll keep us awake. I have found nothing yet that makes me glad I’ve come to do this job!’
Testing and service plans
Testing and commissioning of Section 1 is planned in four phases, and trials with specially-configured Eurostar trainsets drawn from the North of London fleet will begin in January 2003. This should allow Section 1 to open with the summer timetable change in May 2003; it will slash 20min off journey times between Waterloo International and the Channel Tunnel.
When Section 2 is opened in 2007, another 15 min will be trimmed off international timings, and by then the first domestic commuter services should be ready to use the line.
Plans are now being drawn up for initial service patterns once the line is complete. In peak hours there will be eight international trains each way, of which six will serve St Pancras and two will run to and from Waterloo. Stopping patterns for Ashford, Ebbsfleet and Stratford have yet to be finalised, but one train calling at Stratford is likely to continue to the West Midlands, perhaps finally allowing the North of London Eurostar sets to do the job they were built for 14 years earlier.
Union Railways is contracted to provide capacity for eight peak-hour domestic trains an hour on S2, of which two will originate in North Kent and the rest from Ashford and East Kent. Four of these trains will call at Stratford. Off-peak there will be four trains an hour, two each from North Kent and East Kent or Ashford.
TABLE: CTRL Section 1 contracts
330. East Thames: Medway Valley & Waterloo connection (16·8 route-km)Alfred McAlpine Construction/AMEC Civil Engineering Ltd JVAwarded October 1998 ú80m
350. Medway crossing (1·34 route-km) Eurolink Joint Venture (Miller Civil Engineering, Dumez-GTM, and Beton und Monierbau)Awarded October 1998 ú30m
410. North Downs tunnel (7·5 route-km)Eurolink Joint Venture Awarded October 1998 ú80m
420. Mid Kent. Boxley to Lenham Heath (19·8 route-km)Hochtief (UK) Construction/Norwest Holst Construction JV Awarded March 1999 ú85m
430. Lenham Heath to Ashford (15·2 route-km)Skanska Construction UKAwarded October 1998 ú150m
434. Railway infrastructure modificationsJ Mowlem & Co plcAwarded April 1 1999 ú60m
440. East Kent. Ashford (Sevington) to Cheriton (15·75 route-km)Balfour Beatty Major ProjectsAwarded April 1 1999 ú75m
550. Signalling, train control & communicationsCSEE Transport/Corning Communications/Amey Rail JVAwarded February 22 2000 ú56m
552. Ashford resignallingWestinghouse SignalsAwarded December 1 1998 ú6m
570. Trackwork, catenary, mechanical & electrical systemsAMEC Spie Rail Systems LtdAwarded January 24 2000 ú120m
CAPTION: The first track for CTRL Section 1 was laid at Fawkham Junction in MayPhoto: QA Photos
CAPTION: Track panels being assembled for use by AMEC Spie at Beechbrook Farm are second-hand from Thyssen-Krupp in Germany. The site will have 14·8 km of track with an arrivals yard, assembly areas and a dispatch yard for the tracklaying and catenary installation trains. Washed and reclaimed ballast suffices for use on the site
CAPTION: Above: A London-bound Eurostar enters Ashford on the existing line as the new viaduct takes shape to carry the CTRL above the Canterbury line and the River Stour
Left: Fitting out of the North Downs tunnel was completed in July, five months ahead of schedule. Trains will run at 300 km/h through this double-track bore
CAPTION: Designed to match the parallel motorway bridge, the CTRL Medway Viaduct will be completed this month. Carrying the rails 37 m above the river bed, the viaduct is 12·9 m wide, with 4·5 m track centres. The trapezoidal box girder has a width of 5·7 m at the top flange, and the top shoulder of the pier column is approximately 31 m above the river bed
CAPTION: All civil engineering work has been completed on this cutting on Section 1, just west of the Medway crossing, with the bottom subgrade prepared for the start of tracklaying in the next few months
CAPTION: Immediately west of Eurotunnel’s Cheriton terminal, the two tracks of Section 1 take separate routes around the Dollands Moor freight inspection yard. They rejoin to meet a single-track freight connection in a new landscaped cutting above the present Saltwood tunnel, and then parallel the existing tracks as far as Ashford