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Thameslink – the final countdown

With just a few months to go, including two major commissionings, the rebuilt, remodelled and resignalled London Bridge becomes fully operational on 2 January 2018. The Thameslink service resumes through the high level station via the new segregated alignment between Blackfriars and Bricklayers Arms Junction, engineered into the remodelled layout as a key objective of the project together with the introduction of Automatic Train Operation (ATO) overlay to ETCS.

This highly complex and challenging capacity-improvement project, conceived by British Rail’s Network South East back in 1990 when passenger numbers were rapidly outstripping the capacity of Thameslink’s inaugural service of six trains per hour, is nearing completion on time and budget.

Network Rail recently invited Rail Engineer along to hear project director Mark Somers describe the plans for the final two big blockades taking place this year, and to meet the team fitting out the track, signalling and electrification at the south-eastern approach to the station.

Already complete

To date, all six terminal platforms at the low level are open and through-Platforms 7, 8 and 9 are currently in service for Charing Cross trains. Whilst Costain, the contractor rebuilding the station, continues to work on preparing Platforms 1 to 6, and the remaining one third of the street level concourse below is off limits to the public, Cannon Street services are passing non-stop through Platforms 1 and 2.

Essentially, all major demolition and construction works are complete at the high level with all the new bridge decks in position. Behind the hoardings, escalators and lifts are being installed in readiness for the complete concourse opening in January 2018, with retail unit fit-out and other concourse and passageway works continuing through to May 2018.

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August blockade

On Saturday and Sunday 26/27 August, the Cannon Street and Charing Cross lines close, as do low-level Platforms 10 to 13, to facilitate a major signalling data changeover and commencement of the track remodelling described below. Low-level services will use Platforms 14, 15 and line 11 only, as lines 9 and 10 are shut to provide protection for the adjacent track slew works.

For a week from Bank Holiday Monday 28 August, the Charing Cross lines remain shut but services are restored to Cannon Street (trains again running non-stop as the concourse below isn’t ready) and all the low-level platforms. During the period that Charing Cross is closed, Southeastern trains will run from Lewisham to either Blackfriars, Victoria or, via Linford Street Jn and the curve formerly used by Eurostar, into the Waterloo International platforms that will be temporarily reopened for the duration. By Saturday 2 September, all track, signalling, and traction feeder section testing will be complete, allowing test trains to run during this day, with any snagging attended to overnight once the possession has been re-taken. All lines are to open on Sunday 3 September.

Charing Cross services are currently using lines 3 and 4, facilitated by temporary slews near London Bridge and at New Cross respectively. These slews will be removed during the blockade, and Platform 6 brought into service.

At the country end of the station, new switches and crossings (S&C) will be installed in order to connect Up lines 6, 7, and 8 to Platforms 6 and 7 (Down), and 8 and 9 (Up), thereby providing full flexibility in the final configuration of two platforms for Charing Cross trains. Previously, at the London end of the station, with Platform 6 unavailable, a temporary crossover was provided to allow Platform 8 to be used in either direction to suit the tidal flow (typically Up in the morning peak and Down during the evening). This crossover is being removed.

At the New Cross end, no new S&C is needed where the Kent Fast lines will be re-aligned to pass through the new Bermondsey Dive-Under (built by Skanska), meshing into lines 6 (Down Charing Cross), line 7 (Charing Cross Reversible) and line 8 (Up Charing Cross).

Lines 3 and 4 will then be taken out of use and resignalled in the original direction with line 3 reverting to its original purpose of Up Canon Street, and line 4 becoming the new Down Thameslink. A new signal gantry is to be craned in during this phase of the work.

Assets commissioned/decommissioned during this period include:

  • S&C point ends: 19 new, 2 removed, 20 clipped and padlocked;
  • Plain line: 9.7km installed (lines 6, 7, 8), 8km removed (lines 3,4);
  • Signals: 37 new, 23 recovered;
  • Track circuits: 65 new, 36 recovered;
  • AWS: 36 new, 18 recovered;
  • TPWS TSS/OSS loops: 45 new, 25 recovered;
  • Location cases: 24 new;
  • Disconnection boxes: 63 new;
  • REBs: 13 new.

Christmas 2017

From Saturday 23 December 2017 through to the morning of Tuesday 2 January 2018, all the Cannon Street, Charing Cross, Thameslink core, and high-level platforms lines will be closed. The low-level remains open except on Christmas Day and Boxing Day.

Line 3 reverts to its original purpose of Up Cannon Street whilst lines 4 and 5 become the Down and Up Thameslink respectively.

The new Down and Up Thameslink lines will mesh into the platforms 3, 4, 5 and 6 at London Bridge and utilise Platforms 4 and 5 for Thameslink services. These lines run atop the Bermondsey viaduct and on to New Cross Gate via Bricklayers Arms Junction.

The final line through the Bermondsey Dive-Under, called the Southwark reversible, also comes into service, and remodelling, resignalling/re-control will take place at Blackfriars. Extensive data changes are necessary overall to update the interlockings, GSM-R, workstations and to fully enable ETCS/ATO.

The Thameslink core stations will be fitted out with platform ramps to allow for level access onto the carriages of the Class 700 trains. Waterloo International will open again temporarily for the diversion of Southeastern trains.

On 2 January, all lines will be available for the full service.

Installing S&C

Balfour Beatty is the principal contractor undertaking the track and civil engineering work. From London Bridge to Bricklayers Arms, the railway is elevated on masonry arches interspersed with metallic and brick arch road bridge structures, so, in order to keep loadings within acceptable limits, it has been necessary to utilise the much lighter Kirow 250 cranes in tandem lift mode. Tandem lifting with the smaller cranes required the development of a new Lightweight Lifting Beam, saving weight as opposed to the standard Modular Self Levelling Beam and meaning that tandem Kirow 250 cranes can lift a concrete bearer FVS switch panel without using props, which speeds up installation.

Design philosophy that all S&C will be located on straight alignments has substantially been achieved and most S&C is of ‘modular’ design and delivered using the Kirow Tilting Wagon System. This modular S&C is being procured, via the Network Rail Route Services organisation, from manufacturers Vossloh Cogifer UK and Progress Rail.

All engineering trains, provided under Route Services haulage contracts, generally operate out of Hoo Junction Yard and, occasionally, Eastleigh. Network Rail Infrastructure Projects ensures that these critical logistics resources for plain line and S&C renewals are carefully managed and de-conflicted across the country around major bank holiday weekends.

Electrification

Life-expired 100/106lb conductor rail has been replaced with new 150lb/yard rail. New Controlled Track Switches (CTS) have been installed at key locations to enable isolations to be effected remotely without staff needing to operate hook switches and, where appropriate, some hook switches have been replaced by track isolating switches which are operable from the line-side rather than on track.

A new DC traction substation has been built within the arches at London Bridge to replace the existing Track Paralleling Hut (TP Hut). Impedance bonds are Bombardier B3 3000 Impedance Bonds to Spec BR 863 Type 3.

S&T systems

Modifications and extensions to the Cannon Street, Charing Cross and London Bridge central workstations, involving extensive data changes, will be undertaken during the blockades. The workstations are of the Siemens Controlguide Westcad PC-based control and display system.

Provided by Network Rail Telecommunications (NRT), fibre optic data communications networks utilise the Fixed Telecoms Network (FTNx) and, using Cadlock protocol and Cisco routers, link the Westcad at Three Bridges Rail Operating Centre (TBROC) with the Westlock interlockings located at the London Bridge equipment room.

To ensure resilience, a virtual private network has been created, known as Thameslink Signalling Private Network (TSPN), which provides for alternative paths between the ROC and London Bridge equipment room. Fibre-optic cables link the Westlock interlockings with the new Westlock trackside systems zone controllers located within the REBs. These are connected by conventional hard-wired cables to signals, points, AWS, TPWS and other equipment.

Bombardier EBI Track 400 track circuits are used for train detection with Cembre rail terminations. Unipart Dorman integrated lightweight signals (iLS) are used as these have a narrow three-degree beam, well suited to the multiple parallel tracks on the approaches to London Bridge where SPADs have occurred in the past through misreading or reading-through.

Vortok Modular AWS inductors are provided. The lid of the electromagnet is white instead of the usual dark green, to reduce solar gain as protection for the ECU that is provided to maintain the maximum current draw to 1.6 amps, balancing current draw against temperature to maintain flux density. This is to protect the Westlock trackside system which directly drives the AWSs.

In-bearer Rail Point Clamp Locks are used with the hydraulic actuation systems provided by SPX Rail Systems. Signalling power supplies are 650V DC dual end-fed with auto reconfiguration, Class II.

Relocatable Equipment Buildings (REB) house much of the lineside equipment. Some existing signal gantries have been re-used, with strengthened foundations and tie rods, giving improved access for staff including the bolt-on galleries for new signal heads, manufactured by Lundy and installed by Balfour Beatty.

Innovative CEMEX EG53 and GV54 cable management sleepers enable DC traction and signalling cables to cross the track without cluttering up the ballast cribs and removing the risk of tampers damaging cables.

Stretcher bars

In the aftermath of the serious derailments at Potters Bar (2002) and Grayrigg (2007), Network Rail embarked upon a national roll-out of an innovative new design of tubular point stretcher bar (TSB) that has been designed to manage the forces that can be applied to a switch layout by the passage of a train or by the operation of the point operating equipment. The tube is designed to allow the length to be adjusted, and the stretcher bar fitted in the first position also features kicking straps that limit the amount the switch rail can rise.

At the end of each bar, the motion units are articulated to allow the stretcher bar to deal with switch creep and twisting when switches are thrown. If flange back contact occurs, the orange polymers within the motion unit absorb the forces without causing damage to the rest of the system. The retaining plate applies a compressive pre-load onto the polymers.

If the points have been run through, the retaining plate in the motion unit will bow towards the four-foot and the tube will bend upwards slightly.

There are five different types of tube, and four different types of motion units to suit the type of rail section used and the point operating equipment it is being fitted to. TSBs have been fitted throughout the project and are supplied by Howells Railway Products, Progress Rail Services UK and Tinsley Bridge Rail. A kit of specific tools is provided by Lawton Tools Rail Products and is used in conjunction with existing torque wrenches.

Enhancing reliability

A fault in the signalling system at London Bridge may quickly lead to a long queue of trains with thousands of passengers delayed, not to mention Network Rail incurring substantial Schedule 8 penalty payments. Whilst the new TBROC workstation controlled signalling today has much the same ‘entrance/exit’ (NX) route setting functionality as the 1975-vintage NX panel, technological improvements provide for a more reliable railway by means of the duplication of digital systems, and provision of remote condition monitoring (RCM) to pre-empt potential failures that may stop trains.

Setting routes in the large old relay interlockings involved electrical circuit paths spanning many relay contacts. Any single high-resistance relay contact could stop the job. However, there are three individual processing lanes within a Westlock Central Interlocking Processor (CIP), providing triple modular redundancy. This means that, should one processing lane fail, the control function can continue to operate as normal with no interruption to the train service, safety being maintained by mutual agreement of the two ‘good’ processing paths.

For external equipment such as points and track circuits, RCM monitors pump pressures of Clamp Lock points and certain electrical parameters of EBI track circuits. The results are reported to the maintenance unit’s back office, where a data analyst (known as a flight engineer) can initiate a fault log in the event of deviation from normal values.

Nevertheless, the harsh unremitting environment of the railway is such that point and track circuit failures do occur from time to time. Installed on the Thameslink line of route, and all controlled signals in the resignalled area, is the innovative ‘Proceed on Sight’ aspect known as the POSA signal. In the event of a track circuit failure, the signaller may over-ride this by selecting a POSA route, which displays two flashing white lights at 45º to the driver who may proceed cautiously, thereby obviating the delay incurred in stopping at a red signal and contacting the box for permission to proceed.

A track circuit failure may also prevent route locking from releasing behind a train, thereby holding points in the wrong position for other trains. A special Electronic Point Route Locking Release permits the signaller to free and move points in such circumstances. Alas, there is no quick fix for lost detection on points, which will require rectification before any signal reading over the points can be cleared.

Improving access

A visit to the lineside reveals a lack of the usual S&T equipment location cases and REBs. With eleven intensively used parallel tracks on the approaches to London Bridge, access for faulting and maintenance is challenging. Thus, the equipment is concentrated into a series of REBs which are located within the arches of the viaducts beneath the tracks (with the exception of one REB which is at track level at the site of the long-closed Spa Road station) and provide technicians with a weatherproof environment away from the live railway.

EBI track circuit transmitter and receiver units are mounted with protective covers in the four-foot. Signalling Lock-out Devices (SLODS) are provided throughout the London Bridge area to enable access to track-mounted equipment by blocking one line without the need to set up complex protection for crossing and re-crossing multiple tracks.

ATO goes live

With the infrastructure ATO equipment and ETCS level 2 data incorporated into the new interlockings going live in January 2018, the capacity improvements are complete to meet the 20tph (trains per hour) milestone in May aligned with the timetable change, with traffic management deployed later in the year and a period of introduction running prior to realisation of the full 24tph service.

During May 2018, the Lewisham area, along with the Hayes line, is scheduled to be re-controlled to a new workstation at TBROC. In Easter 2019, the Angerstein area, including lines from Charlton and Woolwich to London Bridge via Greenwich and North Kent East Junction, will be resignalled and re-controlled. Finally, in 2020, the remaining Hither Green area controlled by the London Bridge Area Signalling Centre will be re-controlled to a further new workstation, allowing the box to be closed after over forty years in service signalling trains in this highly complex area.

Thanks to Mark Somers, project director; Simon Pears, project engineer; and Alexandra Swann, communications manager for Thameslink, for their help in the preparation of this article.

This article was written by David Bickell.

Read more: Review – Institute of Rail Welding Conference 2017

 

 

Review – Institute of Rail Welding Conference 2017

The Institute of Rail Welding (IoRW) was founded 15 years ago by Railtrack as one of the more positive outcomes that followed from the shocking Hatfield train crash in the year 2000. The idea for the IoRW is attributed to Simon Hardy, then one of Railtrack’s track engineers and now working for the ORR. The Institute has been a great success, and has contributed significantly to the massive reduction in the number of weld failures and broken rails that has been achieved on the rail network.

The Institute was the result of a collaboration between Railtrack and The Welding Institute (TWI), without whose expertise in welding the venture would not have succeeded. Fortunately, the IoRW initiative was taken forward by Railtrack’s successor, Network Rail.

The affiliation of the IoRW with TWI also has the benefit that it is able to offer its members professional registration with the Engineering Council at the appropriate level – EngTech, IEng or CEng.

The celebratory conference was held in York, in association with Network Rail and the National Railway Museum. The morning consisted of a number of demonstrations related to rails and rail welding, and took place at Network Rail’s new complex in the Engineer’s Triangle.

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Demonstrations

French supplier CTF and Network Rail jointly demonstrated CTF’s Translamatic 152 wire feed arc welding repair system. This is capable of carrying out automated repairs to worn rails and S&C components, taking as little as one hour to repair a typical crossing. This includes the crossing nose and both wing rails, and leaves the crossing ready for finish grinding before being returned to traffic. The whole welding cycle is controlled by the software in the control unit – the operator selects the appropriate cycle for the task in hand before leaving it to complete the weld automatically.

CTF offers a full package of equipment to power and support the welding unit, including a caterpillar-tracked transporter with a built-in three-phase generator which feeds the inverter that supplies the welding current.

Thermit GB was another demonstrator that has an interest in the use of higher voltage power on site. Its Smart Weld aluminothermic welding system, incorporating Smart Weld Jet, Smart Weld Record and Smart Weld Ace, uses atmospheric air instead of oxygen to burn the propane fuel to pre-heat the rail ends for welding. Like the CTF system, this one is controlled by computer software, ensuring that the flame is perfect and that correct timings and temperatures are adhered to. All the weld pre-heat parameters can be entered into the Smart Weld app using Bluetooth to connect the pre-heater to a mobile device for this purpose.

The actual weld is made using Thermit’s already well-known systems, so those details are entered via bar codes on the materials used. The associated water mist weld cooling system ensures faster, controlled cooling of the weld after shearing, and will save around 15 minutes on the time taken to complete a weld. This could be very valuable under restricted track access conditions such as are increasingly common on the UK’s rail networks.

Railtech, another French company, was also showing off its latest products in Network Rail’s new workshop, specifically designed and built for welding training. Its HWR rail defect repair system uses aluminothermic weld technology to repair a rail after a defect has been removed by cutting out a semi-circular piece of the head. Railtech also offers computer control of the process, this time via its ‘gas box’ control box, which governs the pre-heating process.

The Railtech team also demonstrated completion of a weld, including the Startwel ignition system and new hybrid felted weld moulds. The latter make it quicker, easier and more reliable to seal the moulds to the rails, and can be easily modified to compensate for rail wear.

Hybrid grinding

German rail equipment manufacturer Robel showed its 13.49 modular rail grinder together with the associated power pack, model 70.02. The grinder is for weld finishing and similar rail profiling operations, whether associated with rail joining or rail weld repair. The grinding head depth is precisely controlled and the head pivots about the rail on a fixed frame, enabling accurate control of rail profile achieved.

The power unit is a hybrid device which stores energy from the idling grindstone and releases it during grinding. This allows the power pack to have a smaller motor-generator unit. Although the combined weight of grinder and power pack is greater than a conventional integrated unit, but each unit separately is light enough to be safely lifted by just two people. The power pack also has the potential to drive other Robel machinery such as weld shears.

Innovation

Trueflame was also present, displaying a wide range of equipment for welding, gas cutting and related purposes including specialist PPE for welders, BV1000 accessories and wire feed systems.

British Steel showed its Zinoco corrosion-resistant rail, and demonstrated how this coating can be removed where welding is required, and then replaced afterwards.

There was a small demonstration from TWI of a rail and weld ultrasonic inspection system which deploys a 64-element head generating a divergent beam. The system for analysing the returned signals allows inspection of a much larger volume of the rail than previously possible, and so can obtain equivalent results to a conventional ultrasonic flaw detection system whilst scanning at 30mm intervals, compared with the normal 1mm interval. As conventional ultrasonic rail flaw detection trains can travel only up to 40mph, this might be a major benefit.

Network Rail’s John Hempshall showed Rail Engineer the ESAB wire feed welding equipment similar to the units specified for the company’s new maintenance trains. These will be the ESAB Warrior welding set and the 301ABS wire feed unit – a neat device that is fitted into a briefcase-sized ABS case.

Inspiration

After lunch, the day continued with presentations by several speakers. The first was David Godley, head of engineering capability at Network Rail. He has only recently taken on this new role, working for chief engineer Jon Shaw. He gave his keynote address on the theme “Innovation & Inspiration”.

David referred back to 17 October 2000, the day of the Hatfield derailment, and spoke of the great changes that have followed. Rails have changed, with CEN60 replacing CEN56 for most main line applications, and aluminothermic welding has also improved significantly – thanks to the IoRW, suppliers and others.

As a keen cyclist, David used the analogy of a bicycle wheel, strong and light as long as it is not abused by, for example, excessive stresses caused by potholes. Rails are the same, and cannot be expected to survive if abused by poor track conditions or significant wheel flats.

David also explained a little of his new role, managing engineering capability across all the engineering disciplines in Network Rail. He and his team are putting into place an “authority to work” process, based upon individual competence, and taking this back from the human resources function into engineering where it belongs. There will be a single competence framework for all professional engineers and asset managers in the company.

He described the need to focus upon safety, compliance and performance, and the imperative to maintain a balance between these three, rather than letting any one of them dominate at the cost of the others. He also covered business-critical rules, and the conflict between eliminating human error from systems to make them safer and the risk that, if this is taken too far, humans become too reliant upon the system protecting them. If that occurs, then disaster may follow through failure to spot a system weakness or flaw, or through human error over-riding the system in some way.

Looking at derailment numbers per annum by failure type, S&C failure is still the greatest risk. Following the latest improvements in welding and rail defect detection and rectification, rail break statistics are now dominated by breaks caused by foot damage and flaws.

David spoke of other initiatives, such as the skills assessment scheme and the six ways to maintain competence, the plain line pattern recognition project and the introduction of under-sleeper pads.

He concluded with some of his ideas about the future of society and of rail.

Reflections on the past

Brian Whitney, chair of the IoRW management committee, followed, presenting some of his reflections on the past 15 years. Brian has to take a great deal of credit for his own contribution to the IoRW and the successes Network Rail has had in significantly improving its rails and rail welds performance in this period. He was far too modest to say this, of course, but it is worth saying here.

Brian described, as we have heard before, the dramatic fall in rail break numbers since 1998/9, from 952 in 1998/9 to the latest figure of only 94 in 2016/7, the lowest ever result.

He referred to the Bushey derailment (abvoe) on16 February 1980, caused by a failed weld, which went undetected until the sleepers under it collapsed badly enough to derail an express train. Fortunately, despite some serious injuries, no one died. He looked at the report of the formal inquiry and the causes identified by this. These ranged from technical items like the incorrect positioning of the moulds when the weld was made, to organisational and administrative matters such as the lack of adequate resources and insufficient supervisory attention.

The need for a greater sense of craft pride and skill was mentioned, very relevant to David’s fear of making things too dependent upon some inhuman system and making people feel they are no longer responsible or in control. Records, skills and training, standards and auditing were all mentioned as issues. These matters are all just as relevant today, despite all the improvements that have been made.

Brian moved on to consider the record of rail welding. Like the rail break record, this is excellent, with the trend from 504 failed welds in 1979 to only 13 in 2016. This despite the vastly increased percentage of the network that now has welded rails (CWR). Furthermore, the 2016 figure also includes welds in S&C whilst the earlier statistic is for plain line alone.

The proportion of rail breaks occurring in aluminothermic welds was around 25 per cent for many years, but in the last four or five years this has begun to fall, now standing at 15 per cent. This is better than elsewhere in Europe. Brian considers this is due to better equipment and techniques introduced in the UK in recent years.

With rail defects dropping significantly, other issues are being shown up. Weld alignment problems are assuming greater significance, for example. Dipped welds lead to dynamic forces which cause ballast attrition and, potentially, failures of rail and/or sleepers. Misalignment laterally or rotationally causes wheel/rail contact forces that lead to rolling contact fatigue damage to the rails.

Defects or damage in the rail foot are becoming the most significant rail failure initiators, now that the other ones have been largely eliminated. Since these are hard to detect by the currently available technologies, it is difficult, at present, to remove them before they cause a rail break. Failures of arc-weld rail repairs are similarly hard to detect until they lead to rail failure.

Brian emphasised the importance of using available tools to identify in advance where there may be a problem and deal with it before a failure occurs. Thus, the use of LADS (Linear Asset Decision Support) and track geometry data may point out, say, a dip in the rail where there is no joint. Aerial inspection can be used to examine a site to help identify why a track fault exists or why track geometry is deteriorating abnormally fast. The challenge, as ever, is making management information out of the huge quantities of data available.

Brian concluded by reading out a message from one of the other people who helped to establish the IoRW so successfully – Tim Jessop, retired former Associate Director of TWI and founding Executive Officer of the IoRW. Tim spoke of those who helped start the Institution, Simon Hardy in particular, and of those who came a little later, Brian Whitney, Bill Mosley and Bob Sawdon. He expressed his pleasure at the progress that has been made and sent his best wishes for the future.

Solving MFBW design flaws

Next to speak was Bob Hervey, project manager for mobile flash-butt welding (MFBW) at Network Rail. He spoke of the history of the technique in the UK, going back as far as the Sersa machine of 1986. From there, he briefly outlined his history with the technology, including his past vow never to go near it again!

Despite that, he ended up taking on his current role a little while ago, and has since been trying to understand the problems associated with Network Rail’s MFBW machines, to correct these and to get the machines working as productively and effectively as they should.

When Bob arrived in his role, the machines that had been purchased were giving problems. Acceptable welds were rejected by the computer welding management system, welds were being left incomplete, and there were occurrences of loss of signal and system failure.

Designated K945, the machines were specially built for Network Rail. They were far more complex than other machines from the same stable, used extensively without problems elsewhere, chiefly because of a demand that they should be able to stress as well as weld.

Bob described the steps taken to confirm what it was about this complex design that was leading to the difficulties experienced before his arrival. Eventually, it became clear that it was the system incorporated in the K945s to allow the head to open by 400mm as compared with the 150mm opening of the normal K920 head used elsewhere.

Bob described the steps that are being taken to modify the machines to eliminate this problem and make them perform. The seventh unit has been modified through a proper engineering change management process and full welding approval testing has been done. It will now be used to relaunch MFBW within Network Rail.

A Golden Age

“The Golden Age of Rail” was the title chosen by Daniel Pyke, product marketing manager of British Steel – the company renamed by Greybull Capital when it bought the long products division of Tata Steel UK in 2016. British Steel now produces about 600 kilotonnes of rail per annum in around 100 different rail profiles, and can roll rail lengths in excess of 100 metres.

Daniel considered whether we are now in the Golden Age of Rail, examining what was meant by a golden age, looking at statistics on rail passenger travel, freight tonnages and network growth around the world. The UK, he said, is doing far more with little new network assets, whilst delivering the sort of improvements in such things as rail break statistics that earlier speakers had outlined.

The rail-related challenges that the railway faces include rail wear, plastic flow, rolling contact fatigue (RCF) and corrosion. British Steel has solutions to assist in managing these issues. HP335 rail steel is designed to reduce wear and RCF, and reduce grinding requirements, plastic flow and corrugations, while Zinoco rail coating prevents corrosion and increases durability, and is itself resistant to damage.

Although Daniel considered that this may be the Golden Age, he stated that it is imperative the railway continues to improve in order to maintain competitiveness in the future, implying that tomorrow will be even better than now!

And finally…

It fell to Chris Eady, associate director of TWI and interim executive officer of the IoRW, to round off the day.

While other speakers had looked back at the first 15 years of the IoRW, Chris looked to the next 15 years, speaking first of the proposed IoRW Strategic Action Plan 2017-25. This has four themes:

  • Support for Rail Infrastructure Controller decision-making;
  • Development/implementation of Rail Welding best practice;
  • Delivery of Rail Welding personal competence;
  • General education/awareness of rail welding.

He spoke of the challenge of success – if rail welding becomes so well managed that rail welds cease to be a problem, how does the railway ensure that funding, resources and attention continue to be given to it to make sure that it continues to be problem free?

Chris continued by looking in more detail at the strategic themes and how IoRW might take them forward in order to meet this challenge effectively. In his opinion, immediate action needs to be taken concerning application standards, research priorities and strengthening relationships with rail industry bodies like RDG, RSG, RIS, NSAR and PWI.

All of which will ensure that the Institute of Rail Welding will be around for at least the next 15 years.

This article was written by Chris Parker.

Read more: The world’s longest footbridge?

 

The world’s longest footbridge?

Railway engineers don’t often get the opportunity to dismantle and rebuild a piece of railway heritage. That’s why working on a well-known station footbridge in Anglesey was such an exciting project for Network Rail’s asset engineer and externally appointed structural designers. The work was carried out at the beginning of 2017 as part of the plans to build a bigger and better railway for passengers.

Llanfairpwll station is a popular tourist attraction due to the extended name it is often known by – Llanfairpwllgwyngyllgogerychwyrndrobwllllantysiliogogogoch – which translates to “St. Mary’s Church in the hollow of white hazel near a rapid whirlpool and the Church of St. Tysilio near the red cave”. People visit the station to take photographs of the famous sign and often use it as a starting point to explore Anglesey and the North Wales coast.

Even the name itself is a piece of railway history. It was ‘invented’ in the 1860s to be the longest place name in Britain and to attract tourists. At 58 characters (only 51 letters as ‘ch’ and ‘ll’ are regarded as single letters in Welsh) it is the second longest place name in the world*. To make life simpler for passengers and for ticketing websites, the official name of the station is Llanfairpwll, with the three-letter code LPG.

But back to the bridge…

Philosophy

Whenever possible, when carrying out footbridge refurbishments, the Wales route removes any spans crossing the track and transports them to a controlled environment. Of course, this is only practical where a temporary footbridge can be installed on the site and the general logistics of the surrounding area allow for the hoisting and lifting of a bridge span onto a low level loader.

This philosophy is driven by three factors – the results of inspections of previous bridge refurbishments completed on the Wales route over the last five years, the importance for the control of salt contamination, especially in coastal areas, and the safety of passengers using stations during refurbishment works.

In addition, it was important to work with partners Arriva Trains Wales to ensure that the works were completed during the winter and spring in order to cause minimal disruption, with the station and surrounding area being such a popular tourist destination.

As it was

Network Rail’s structural assessment programme confirmed that the footbridge in Llanfairpwll could not support the minimum required live loading of 5.0kN/m². Considering the station’s high footfall, this was a concern. Therefore, the buildings asset team, based in Cardiff, decided to restrict the number of passengers that could physically stand on the bridge span.

Prior to the Flying Scotsman passing through during 2016, Herras fencing was installed to the deck span to physically minimise the loaded width of the footway. A full repair and refurbishment was imminent, so the installation of this fencing was only deemed a short-term restriction.

A desktop study confirmed that the layout of the station allowed for a temporary footbridge to be installed and the existing span could be hoisted onto a low level loader and transported to a workshop. The footbridge trestles and staircases would remain on site, encapsulated with a scaffold system for full access and covered to protect the structures from the elements during the onsite refurbishment of these parts.

Network Rail tries to avoid any site painting works during the winter months, but negotiating access to the site with third parties took longer than anticipated and delayed the start date for the project.

The lift

During January 2017, a temporary Layher footbridge was installed, complete with a temporary lighting installation and the required lux-level testing. This was all completed and in operation by 19 January.

The existing footbridge was closed and the footbridge structure was prepared for span removal. This included removing the handrails, lighting and the connection fixings securing the bridge to the trestle frames at either end.

The lift was carried out on a Saturday night under possession using a crane and slings. The bridge was slowly hoisted and manoeuvred towards a low level loader in the car park and transported to Centregreat’s workshop in Cardiff, 210 miles away.

The reveal

Once the bridge span had been removed and the bare frame of the structure had been shot blasted back to bare metal, engineers were able to inspect the Victorian structure up close and appreciate the sheer simplicity of the bridge. The overall impression was quite promising and it appeared to be a relatively intact structure.

The inspection revealed that the bottom chord of the lattice truss had previously received strengthening plates, but it wasn’t until the plates were removed that the true extent of corrosion could be seen. Once it was decided that a full renewal was required of the bottom chord, engineers worked alongside Centregreat’s steelwork fabricators to design and detail a new bottom chord that would reinstate the transfer of forces between the top and bottom chord of the truss.

Salt contamination

Even with the strictest of site controls, it is very difficult for a contractor to control the level of salt contamination, particularly in coastal environments. However, the Wales Route did succeed with one footbridge refurbishment during the summer of 2016. The site was located in one of the highest recorded areas for airborne salts and, for logistical reasons, the footbridge could not be removed off site, so the footbridge was constantly monitored, jet washed and retested to prove that salt contamination was within acceptable limits before the application of paint layers.

Although the footbridge span at Llanfairpwll was removed for refurbishment in a factory environment, the stairways and trestle frames had to remain. With full site encapsulation, the trestle frames and stairways were shot blasted back to bare metal ready for repairs and strengthening.

The contractor had to ensure that the soluble salt traces left on the shot blasted on-site structures were monitored and, where required, further jet washing was carried out and tested before each paint layer could be applied.

As well as repairs and painting, the main span of the bridge, the stair treads, risers and landings were totally replaced with structural GRP panels and treads, specially made by Polydeck using its unique foam core support structure which matched the new footbridge span. The GRP deck also provides a durable, aesthetically pleasing and slip-resistant walking surface

Unaligned colour scheme

The specific requirement for the colour scheme was that it should not relate to any branding. Therefore the Railway Heritage Trust developed a suitable painting scheme for the North Wales coast. The architect at the time for the regional railways in the North West generally used dark green, beige and red. These colours, in particular the dark green and beige, worked well with a variety of materials and were well suited to rural locations.

The reinstatement

By mid-March, the structures were completed and about to be reunited. On 25 March, the refurbished span was hoisted and manoeuvred back onto its support trestles. By the 29th, the sparkling footbridge was completely trial lit with new energy saving LED lights, which would eventually be lit within the new handrail system.

The £395,000 project to upgrade and restore this historic footbridge was completed by mid-April. The benefits of the span removal, strict control of salt contamination and an understanding and respect for Victorian heritage were there for all to see.

All that was left to do was to dismantle the temporary footbridge and clear the site, ready for a new season’s tourists to arrive.

Darren McKenna is an asset engineer – buildings fabric on the Wales Route of Network Rail.

*The world’s longest

Those wondering why Llanfairpwll station, at 51 letters (58 characters), is only the world’s second longest place name should visit a hill at Hawke’s Bay. According to Land Information New Zealand, the hill is called Taumatawhakatangihangakoauauotamateapokaiwhenuakitanatahu (57 letters) although there are even longer forms of the same place name with up to 105 letters. It’s 85-character version, Taumatawhakatangi­hangakoauauotamatea­turipukakapikimaunga­horonukupokaiwhen­uakitanatahu, features in the Guinness Book of Records as the longest place name. But locals simply call it Taumata.

This article was written by Darren McKenna.

Read more: An award-winning bridge design in Wigan

 

An award-winning bridge design in Wigan

Carters Bridge was built in 1868 as a two span overbridge comprising steel beams supporting a timber deck. Constructed for the opening of the Lancashire Union Line, it is the only means of access for a farmer between two sections of his land.

By the 1950s, the mass brick abutments showed significant signs of deterioration and were propped by timbers. The distress is likely to have resulted from ground movements caused by historic mining. The superstructure was replaced in the 1960s by a pair of steel beams supporting timber decking. The brick abutments were partially broken down and replaced by bank seats at the top of the railway cutting.

The structure spans the Wigan to Huyton lines, which were electrified in 2012 in Phase 2 of the North West Electrification Programme. However, the structure was found to be understrength and the parapet was inadequate over the electrified lines.

So, in 2015, Network Rail commissioned Murphy and Tony Gee and Partners to design and construct a replacement bridge. The GRIP 2 document (feasibility) stated that the bridge would be replaced by a two-span steel composite structure supported in the existing abutments. This solution required extensive temporary works and would cause considerable disruption to the farmer’s business as it would have required a 10-week closure of the bridge.

Instead, the team developed a 39-metre single-span solution, to be constructed parallel to the existing bridge. This minimised the disruption to the farmer as the new bridge could be built while maintaining access using the old bridge. However, the design team was constrained in two ways – only two 29-hour closures of the railway would be permitted for the scheme, and the new structure would have to be installed over the electrified railway.

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Ground conditions

The bridge is situated on the Pennine Lower Coal Measures Formation (PLCM) of the Langsettian age of the South Lancashire Coalfield, composed of sandstone, siltstone, mudstone and coal beds. Covering this solid geology there is a thin veneer, less than a few meters thick, of superficial glacial deposits (diamicton).

Due to historic mining activity in the area and the predicted presence of coal seams beneath the structure, a comprehensive site investigation was undertaken. The ground investigation comprised eight boreholes to depths of between 31 and 40 metres. A combination of rotary coring and open hole drilling was employed, with the objective of providing geotechnical information for foundation design and checking for the presence of worked or unworked coal seams beneath the structure.

The materials encountered in the boreholes generally corroborated the anticipated superficial and solid geology from the desk study, which had been developed based upon the examination of geological maps and borehole records in the public domain.

The proposed north abutment founding level was confirmed as being situated, in its entirety, in an eight-metre-thick layer of ‘extremely weak’ to ‘weak’ mudstone. The intact coal seams and various lithologies encountered in the four boreholes located on the northern side of the cutting could be readily correlated.

However, correlation of the materials encountered in the boreholes situated on the southern side of the cutting was extremely difficult, with boreholes only 10 metres apart showing significant differences in stratigraphy. These differences were explained at design stage by the presence of two mapped geological faults in close proximity to the location of the south abutment, one was noted to be ‘uncertain’.

Irrespective of the aforementioned, the two boreholes closest to the position of the south abutment both gave the founding level stratum to be a ‘medium-strong’ sandstone of variable thickness.

Foundation design

Having assessed the results of the geological survey, both abutments were designed with shallow foundations, the north abutment on mudstone with an allowable bearing pressure of 320kPa and the south abutment on a sandstone founding stratum with an allowable bearing pressure of 1,000kPa.

Due to the variability detected in the boreholes, a risk was identified that the founding stratum could vary from that anticipated in design. Consequently, once the excavations were nearing founding level, they were inspected and mapped to confirm they complied with the minimum acceptable geotechnical conditions in terms of rock lithology, strength and degree of fracturing identified on the drawing.

Preliminary calculations were also undertaken for the south abutment to confirm that, in the event that the actual founding stratum was a mudstone, a workable shallow foundation solution could be found without the necessity to revert to piles.

Bridge deck solution

Tony Gee developed a concept where the main weathering steel beams would be lifted into place with the stringcourse and parapet in place. This removed the requirement for temporary works over the railway during construction and allowed the bridge to be installed in a single 29-hour closure of the railway.

A 3D BIM model was used throughout the design process to facilitate buildability discussions within the delivery team. This concept was developed by Tony Gee working in close collaboration with Murphy International (steelwork fabricator) and Shay Murtagh (pre-cast concrete manufacturer).

The two pairs of beams were fabricated with the stringcourse in two sections in the precast yard to allow delivery. These were spliced together on site and a small in-situ stitch section was cast in the stringcourse at ground level. The aluminium parapets were installed prior to lifting.

The entire substructure was designed to be precast as modular elements to limit lift weights.

Innovation

To enable the pair of girders, stringcourse and parapet to be lifted as a single unit, the stringcourse was designed as a continuous upstand. This provided lateral stability to the main beam during installation. It required innovative collaboration between the fabricator and designer, ensuring the units could be fabricated in two pieces and then transported to site in Wigan.

To communicate the new bridge construction process effectively, a QR code was added to information posters. This allowed site team members and site visitors to scan the QR code which redirected them to a website which had an interactive 3D installation model for the bridge. This displayed a user-friendly, step-by-step installation procedure enabling people to fully understand each stage in the construction process.

Environmental management and sustainability

The environmental management plan (EMP) was developed at the earliest opportunity, ensuring that requirements of key stakeholders, including the operators of a buried fuel line which crossed the site were identified and addressed.

All legal requirements were met prior to the start of construction. This included obtaining a hedgerow removal notice from St Helens council to allow for the widening of the site access for the transportation of the crane to site. In addition, a T7 exemption was obtained which would allow for the crushing and screening of bricks from the demolished abutments on site. This diverted 500 tonnes of waste from landfill as the material was reused in the reinstatement of the bridge approach slopes and for use as hardstanding via U1 exemption.

Completed scheme

The main beams and entire new substructures were installed in a single 29-hour possession using a 1,000 tonne crane. On completion, the stone for the crane berthing area was reused for the approach roads.

The scheme was successfully completed in May 2016 through close collaboration between the designer and contractor and by an innovative challenge to the GRIP 2 proposal.

The scheme was subsequently awarded Medium Project of the Year at the ICE North Awards 2017. Darrell Matthews, North West regional director of the Institution of Civil Engineers, said: “The new Carter’s Bridge is a great example of how civil engineers solve problems. In this case, an old bridge had to be replaced while causing the least possible disruption to the people who needed access to it and the railway that passed under it.

“The engineers achieved this by ingenuity in design and construction, including the prefabrication of bridge components off-site so they could be installed using a large capacity crane during a single 29-hour closure of the railway line.

“Meanwhile, the old bridge was left in place while the new one was constructed, after which the old bridge and the remains of an even older structure were demolished. The whole thing was delivered on time, on budget, with an excellent safety record and minimal impact on the environment.”

This article was written by Lee Barraclough, associate director at Tony Gee and Partners. Additional material kindly supplied by Delyth Bowen of J Murphy & Sons.

Read more: Holding back the tide at Cobb Valley culvert

 

Holding back the tide at Cobb Valley culvert

The railway network includes some stunning structures, built by the foremost engineers of the day.

The list includes the Royal Albert Bridge between Devon and Cornwall (IK Brunel, 1859), the Royal Border Bridge in Northumberland (Robert Stephenson, 1850), Forth Bridge (Sir John Fowler and Sir Benjamin Baker, 1890), Glenfinnan Viaduct, Inverness-shire (Robert McAlpine & Sons, 1901), Ribblehead Viaduct on the Settle-Carlisle line in North Yorkshire (John Sydney Crossley, 1875) and the Twemlow Viaduct in Holmes Chapel, Cheshire (George W Buck, 1841).

There are even some modern ones. The Medway Viaduct (HS1, 2003), and Loughor Viaduct in South Wales (Carillion and Tony Gee & Partners, 2013) are good examples.

In a list published in 2013, Network Rail identified 28,451 bridges in its portfolio, excluding footbridges and culverts. It commented: “A bridge is defined as a structure with a span of ≥1800mm.”

Small and unseen

But what of the ones under 1800mm? Often overlooked, and certainly not iconic, these are the drains and culverts that run under the railway all over the country – around 30,000 of them, just on Network Rail infrastructure. They have to be maintained, they may well have water running through them either constantly or in times of flood, and any problems with them may well go unnoticed until it is too late.

Like most marine structures, culverts are simple, but can become damaged and dangerous with water erosion over time. A good example is the Cobb Valley Culvert in Anglesey, North Wales. This runs directly under the A5 highway and North Wales Coast railway between Valley and Holyhead, adjacent to the Cymyron Strait. With water flowing through the structure at approximately four metres per second (nine mph), the high flows and poor conditions prevented any safe means of access to carry out inspections and repair works.

Kaymac Marine & Civil Engineering was commissioned by Network Rail to control the powerful flow of water through the structure so that a structural survey and any remedial works could be carried out safely. However, with the Irish Sea to the north and the inland tidal lagoon to the south of the structure, there is constant flow, making this a challenging operation if not controlled correctly.

Water flows through the structure on both rising and falling tides, with slack water lasting only a very short time – around 10-15 minutes – so this was no easy job for the Kaymac team as the works had to take place at night during blockades of the railway line and within the short window at slack water.

Tidal challenge

To control the water flow, Kaymac designed a steel guide and sluice gate system that would hold the water back and prevent any flow through the structure. Due to the volume of water that flows through the structure during the tidal cycle, the sluice could only be lowered and raised at certain states of the tide lest it became jammed in the steel guides or, potentially, damaged during the operation.

Although the sluice could be lowered and raised using pneumatic winches or manual chain pulls, Kaymac used a crane positioned on the A5 carriageway to ensure that the sluice did not become obstructed through possible un-balanced lifting as a result of using two separate winch systems.

Working against the clock during a Saturday night possession, the specially designed and fabricated steel guides were installed and a sluice gate lifted into position, ready for operation at slack water, using a 25-tonne crane positioned within the road closure on the A5. Slack water was at approximately 02:00 and there was a 10-15 minute window to lower the gate into place, which was successfully achieved.

A stop log system was then installed at the seaward side of the structure at relevant states of the tide throughout the week using a 10-tonne mobile crane working within the temporary traffic management set up on the A5. Following installation of the stop logs and the final sealing, the sluice gate was removed using two six-tonne air hoists during another Saturday night possession; a road closure was in place and a 25-tonne crane on site as a precautionary measure.

The whole structure became totally accessible and, after having been inspected safely by divers, re-pointing and fracture repairs were carried out.

On completion of the repair works, the sluice gate was re-fitted, allowing safe removal of the stop logs. The sluice gate was then raised at slack water, allowing free tidal flow through the structure. The upper steel guides permitted the steel sluice gate to be raised and then fixed into the open position until Network Rail requires further maintenance or inspection work to be carried out in the future.

In this instance, although working on a rail culvert, the Kaymac team called upon its expertise in marine engineering to assist. The company regularly inspects lock gates, installs cofferdams and carries out scour protection work, an activity which is also in demand around rail bridges over rivers and estuaries.

With facilities at Swansea, Bristol and in Kent, Kaymac is well placed to assist with all types of ‘wet’ work and specialises in innovation above and below the water line.

Read more: Swanage Railway Reconnected

 

Swanage Railway Reconnected

The preserved Swanage Railway in Dorset featured in issue 86 (December 2011), which described the control and communications systems and featured the three signalboxes at Swanage, Harmans Cross and Corfe Castle. The article hinted of the intention to extend services to Wareham on the Bournemouth-Weymouth main line, maybe as early as 2013. That was overoptimistic but, since 13 June this year, a regular service has started, the first time since 1972, when BR closed the line, that timetabled trains have run over this section.

Freight services had continued from Worgret Junction, where the branch joined the main line, to Furzebrook for trains associated with the extraction of oil from nearby wells at Wytch Farm oilfield. This was fortuitous, as it maintained the connection to what was then considered a long siding.

The Swanage Railway gradually re-built the line back from Swanage to, firstly, Herston Halt, then to Harmans Cross, and finally through Corfe Castle to Norden. This was established as a railhead for people to park and take the train to Swanage, where traffic congestion was a major concern.

In 2002, the final length of track was laid to join the newly created railway with the Furzebrook siding, thus permitting the occasional special train to visit the line. However, without proper signalling with the main line, there could be no semblance of a regular service.

So why has it taken so long to re-establish the full route for passenger trains and what has been required? Rail Engineer went to meet Mike Walshaw, the project manager for the signalling system between Norden and Worgret Junction, to find out the detail.

Basic signalling requirements

The Swanage Railway uses traditional signalling practice with signalboxes containing mechanical lever frames, semaphore signals, and electric token and tablet machines for the single line sections. The mainly volunteer operators are familiar with this operation and it was decided to maintain something similar for the Wareham extension.

However, with the Poole to Wool main line being re-signalled using modern colour light signals and track circuit block, interfacing the two technologies was always going to be something of a challenge.

The line from Corfe Castle to Norden was originally worked with a train staff, allowing only one train in this short section. At Norden, a run round loop exists for the steam service loco to run round its train, and is a continuing requirement.

This method of train staff working would not be appropriate for any onward service to Wareham and thus, when the new Corfe Castle signalbox was commissioned in 2011, the section was converted to NSKT (No Signaller Key Token) operation with train crews being responsible for the token activity at Norden. This set the scene for the creation of a new NST (No Signaller Token) section from Norden to Worgret Junction for the extended service.

The new token section extends from the barrier-controlled level crossing named ‘Norden Gates’, on the London side of Norden Station, as far as Network Rail’s colour-light junction-protecting signal at Worgret Junction (PW5750). To place the London-end token machine on the branch line short of the junction would mean stopping trains there to pick up or give up tokens, which was deemed impractical.

Instead, two token machines are provided at Wareham Station in enclosed location cases at the east end of both the Down and Up platforms. Swanage trains normally use the Down platform but trains can access the Up platform via a crossover should South West Trains’ Weymouth-bound services be running late.

The Poole to Wool section, including Worgret Junction, is controlled from the Dorset Coast Panel at Basingstoke SCC (Signalling Control Centre). This has a carefully designed interface such that the signal leading on to the Swanage branch cannot be cleared unless a token has been taken out for the section to Norden Gates, a workable solution.

Design and procurement of equipment

Much equipment was required to allow this extended operation. A newly created level crossing at Norden Gates (see later paragraph) meant that a crossing keeper’s cabin had to be provided. Although this looks like something acquired from another site, it was actually purchased in kit form and is based upon the erstwhile Lyme Regis ground frame cabin – it was erected in a single day.

Signals to protect the crossing are of the semaphore stop type with electric motor operation, together with fixed semaphore distant signals. The cabin has no levers, operation of the signals and points being by rotary switches on the block shelf, electrically interlocked with each other with indicators to show the status of each item.

The line from Norden Gates to Corfe Castle is track circuited and there is a Train Approach Treadle for trains approaching from Wareham to alert the crossing keeper that the barriers need lowering.

Specially adapted Tyers Electric Key Token machines are installed at Norden Gates, plus the two at Wareham, together with 30 newly manufactured tokens for the section. A small number of ground frames to access sidings along the route are unlocked by insertion of the token, including one location which is the road-rail access point for the railway. Should there be a ‘shut inside’ requirement for any of these, then the token has to be returned to Norden Gates by a responsible person.

A 30-pair 0.9mm copper conductor cable has been buried between Corfe Castle signalbox and a signalling-equipment interface with Network Rail, catering for both signalling and telecommunication needs. It connects into a similar Network Rail cable to give communication with the token instruments at Wareham. Direct-line telephones link Corfe Castle signalbox with Basingstoke SCC and the three token machine locations. There are also dial-up phones at Corfe Castle signalbox and Norden Gates, connected to the Swanage Railway telephone network and the BT national network.

Norden Gates level crossing

Passengers intending traveling by train and parking at Norden, also commercial traffic to Wytch Farm Gathering Station, use the level crossing. When only the occasional excursion special used the line, hand-signal flags and moveable barriers were acceptable for controlling the rail and road traffic. However, now that a regular service is being introduced, and with the density of road traffic, it was necessary to provide a full Manually Controlled Four-Barrier (MCB) crossing.

Such a crossing can be very expensive. However, the Swiss company Schweizer Electronic produces a ‘complete’ package based upon an industry-standard PLC (programmable logic controller). The kit comprises all four barrier machines and booms, the flashing light ‘wig-wags’, the audible warnings, plus a lineside cabinet which houses the programmed PLC with all of its line connections and standby power supply. The manual crossing control buttons are contained within a small console mounted on a plinth in the crossing keeper’s cabin.

Whilst the package is a complete entity, it has to be interfaced to the operational railway which, for Norden Gates, proved to be quite complicated. The design was carried out by a signalling expert from another heritage line.

In the Down direction (from Worgret Junction), the control is relatively simple. The crossing is protected by the electrically operated home signal (No 32), which cannot be cleared unless a token for the Norden Gates to Corfe Castle section has been released (by the Corfe Castle signalman), the barriers proven as lowered and the crossing proven as clear.

For the Up direction (from Swanage), it must be remembered that the steam service operates only as far as Norden. There, the locomotive needs to uncouple and proceed to the Engine Release Spur, off the main line leading to the level crossing via a set of motorised points, before running round its train. This procedure does not require the presence of the crossing keeper or the barriers to be lowered, even though the loco gets very close to the crossing. Its movement is controlled by an electrically operated shunt disc signal (No 5), which can be set to clear automatically after a timing sequence. The token for the Corfe-Norden section is then used by the train crew to unlock two ground frames so they can change the loop points at each end.

The through train service needs a different procedure. On approaching Norden station, either by the occupation of a track circuit or, for stopping trains, by the platform staff operating a ‘train ready to start’ (TRTS) plunger, the prompt for the barriers to be lowered is given. The crossing keeper will have set the points for the level crossing and the Corfe Castle signalman will already have released to him a token for the Norden to Worgret section.

The crossing keeper, when prompted, lowers the barriers and clears semaphore signal No 4 for the train to proceed over the crossing and on its way. Tokens are exchanged with the loco crew by the crossing keeper, who has been provided with token-exchange platforms to facilitate this operation.

There is a need to minimise the time that the barriers are lowered, hence the different prompts for barrier-lowering to achieve as short a time as possible. Barrier raising is manual, by pushing a single button on the console.

Since the primary reason for the crossing is road access to Wytch Farm Gathering Station, BP generously contributed to the cost of the system, for which the Swanage Railway is very grateful.

Trains and rolling stock

Because the trains to Wareham operate over Network Rail tracks, they must have main line certification. This entails the provision of AWS/TPWS, GSM-R radio and on-train data recorders, as well as having the correct wheel profiles and maintenance certificates.

The Swanage Railway has a Class 117 three-car diesel unit and a Class 121 single (bubble) car, both being earmarked for the new service. Whilst preparatory work has been undertaken, unfortunately it was not possible to complete the work for the 2017 trial Wareham Service. Coming to the rescue has been West Coast Railways, which has hired out Class 37 and Class 33 diesel locos to top and tail a hired four-coach set. West Coast staff are in attendance to familiarise Swanage train crew with their locomotives.

Now that the service has started, Swanage crews drive and manage the train and this arrangement will remain in place for 2017. Next year should see Swanage Railway’s own DMUs operating the service.

Commercial considerations

The 60-day trial service has seen respectable loadings so far, although it is recognised that a certain novelty factor exists. The trains provide four services a day until 3 September, running at two-hourly intervals on Tuesday, Wednesday, Thursday, Saturday and Sunday. The turn-round time at Wareham is only nine minutes, so as to minimise any potential interference with South West Trains’ services. Fitting this in with the two-train steam service to Norden, which operates every day in the Peak Timetable, is carefully planned, with trains crossing at Corfe Castle or Harmans Cross as appropriate.

At Wareham, a separate Swanage Railway ticket office has been set up near to the main entrance and the platform indicators are programmed to show the Swanage services. It is hoped that the service will become a regular feature of the area’s transport plans, offering new opportunities for locals and holidaymakers in the Bournemouth, Poole and Weymouth localities. In 2018, 90 days of operation are planned.

Some future plans

Norden Gates is manned by a crossing keeper, who has to be on duty all the time the Wareham service operates. Thoughts are therefore being given to controlling the level crossing remotely from Corfe Castle by CCTV monitoring, which will give greater flexibility.

At Wareham, there are sidings on the London side of the station which could be used for stabling Swanage trains in between South West Trains’ services. Currently, a barrier-controlled foot crossing over the tracks prevents these sidings from being used, but Dorset County Council is planning to provide a disabled-access footbridge over the line which will bring safety benefits all round. Once in place, this could lead to steam services over the extended line.

Operating a service beyond Wareham, perhaps to Bournemouth, is a vision that some have, giving travellers greater access to Swanage. It would mean the Railway becoming an Open Access Operator, so it is very much a long term plan.

Mention must be made of Dorset County Council, which have been very supportive in the reinstatement of the entire railway and which may influence things into the future.

For now, congratulations to the Swanage Railway for its new venture as it joins the North Yorkshire Moors and the North Norfolk Railways as lines which have negotiated running heritage railway trains over Network Rail tracks to a station operated by a franchised train company. May this venture be very successful.

Thanks to Mike Walshaw, Mike Southey and to Fraser White for taking time to explain the operation of the extended line.

This article was written by Clive Kessell.

Read more: Waterloo and South West Route Upgrade

 

Send for the skyhooks! The reconstruction of Albrighton bridge

Credit: David Millar.
Credit: David Millar.

The Victorian footbridge at Albrighton station is a fine structure. It’s Grade II listed and obviously everyone’s pride and joy. Carefully restored in 2013, it is resplendent in its fresh coats of paint, clearly visible from Station Road that passes beneath the station platforms.

Clearly visible eh?

Yup, you can’t miss it with its main span supports smack over the eastern abutment.

Now that’s fine if you’re looking for an historic footbridge from the road, but it’s not that fine if you have the task of replacing the bridge under the footbridge foundations.

The footbridge is in the way.

Credit: David Millar.
Credit: David Millar.

Time for reconstruction

The original bridge under the railway between Wolverhampton and Shrewsbury was constructed in 1849. How do we know with such certainty? Well, it’s written in large letters on the cast-iron parapets that survive to this day. (In fact, the date on the beams is 1848, which is when they were cast rather than when they were installed.)

They, too, are everyone’s pride and joy. They, too, get in the way.

Station Road underbridge is a relatively modest structure. It is heavily skewed and was reconstructed in the late 1890s. This, in turn was reconstructed in 1935. It carries two tracks and the 1935 structure consisted of a central girder and two outer girders with a troughing deck.

The station’s platforms were reconstructed at the same time, with trusty Dorman Long 24-inch deep girders supporting the precast concrete slabs.

In common with many similar structures, it was showing its age and the time had come for it to be reconstructed once again. But, this time, the track-carrying components were not everyone’s pride and joy. Rusting and dripping wet, it was time for them to go.

Amco is Network Rail’s framework contractor on this part of the network. They worked with designers Tony Gee and Partners to reconstruct the 1930s bridge, taking in the complex task of preserving the heritage material. David Millar was Amco’s senior project manager for the work responsible for both managing the design of the temporary arrangement and being the Contractors Responsible Engineer (CRE) on site when it was installed.

All bridges require an element of preparatory works – utilities to check and avoid, and site facilities to set up. However, because of the footbridge and the cast-iron parapets, this bridge reconstruction job had more than its fair share of challenges.

Credit: David Millar.
Credit: David Millar.

Audacious temporary works

Time is strictly limited, even during an out-of-the-rules extended possession. The project was allocated a 73-hour possession but, even within this budget, there was little time to spend scratching around the foundations of the footbridge so that new cill beams could be installed.

The solution was to adopt some very audacious temporary works. A tower was erected tight against the side of the platform retaining wall, heavily weighted with concrete blocks. Beams were then threaded under the top landing of the footbridge, cantilevering out from the tower.

In all, some 19 tonnes of kentledge weights were used in the tower, and this was sufficient for the footbridge to be supported by the cantilever beams. This whole arrangement allowed work to take place below the footbridge footings.

The precious cast-iron parapets were carefully protected so that they would not be damaged in the main possession.

All this temporary work made the site very difficult to work in, so it was important to carry out as much work in the days prior to the possession without affecting the running lines.

Credit: David Millar.
Credit: David Millar.

Road and station closures

With the station closed to passengers for two weeks, the platforms over the road were dismantled and the abutments on each corner were excavated as far as possible, with Amco teams working night and day shifts.

The roadway dips down steeply under the railway which meant that, in order to create a level working platform for the 1000-tonne crane, substantial quantities of Navi Mats (350 in total) were needed to create a working platform for the crane and its outriggers.

All this preparatory work was carried out with a road closure that was taken two weeks before the Easter weekend. This enabled materials to be stockpiled, except for the major items which were transported down from Scotland, after a full scale trial erection, and held at a nearby service station until required to arrive ‘just in time’.

These major items included the large cill beams – 65 tonnes each – and the two Network Rail standard U-decks, each also weighing in at 65 tonnes. The cill beams, manufactured in Ireland by Shay Murtagh Precast, were shipped across to Lanarkshire Welding in Scotland, which fabricated the steelwork, for the trial erection.

Also included were the two new 56-tonne platform units, also fabricated by Lanarkshire Welding, to replace the old platform that had been dismantled. These mated up with upstands on the cill units, and were designed to connect up to the original 1849 cast-iron edge beams, a feature in the design that turned out to be very complex to achieve.

Credit: David Millar.
Credit: David Millar.

Applying Christmas’ lessons

Network Rail’s project manager Stephen Townley was keen to draw on lessons learnt over the Christmas period when overruns had occurred on West Coast main line works. It was a deliberate tactic to make all components as large as practical – after all, there was a 1000-tonne crane available and it seemed logical to use its capacity to the full – and fitting together smaller precast items can often lead to delays, no matter how precisely the items have been constructed.

The main possession started at 01:00 on 15 April 2017. The first task was to remove the track, carried out by 1st in Rail. The rails were cut and drawn back to be reused, while the life-expired timber sleepers were scrapped.

With the track out of the way, it was time to remove the existing bridge structure, which had a central girder rather than being two separate spans. Having examined the logistics of cutting up the steelwork in-situ, it soon became clear that the easiest way forward was to remove the entire structure in one go. Again, Baldwins’ 1000-tonne crane was available, so why not make best use of it?

Sam Evans and Sons of Widnes undertook the demolition of the bridge and the handling of spoil and backfill materials. Lifting beams were positioned below the deck and it was not long before the 87-tonne bridge was airborne. The record drawings proved to be accurate, as the structure had been landed originally on cast bearings rather than being bolted down directly to the abutments.

Credit: David Millar.
Credit: David Millar.

Tonnes of spoil – plus cupcakes!

With the old deck out of the way, excavators set about reducing the abutments down to a saw cut that had been made earlier. Despite the ever-present temporary works, something like 300 tonnes of spoil was loaded away.

Once a level surface having been created on the old abutments, it was time to lift in the large cill beams. To get them to fit into the tight space available took some ‘teasing’ of brickwork. Learning from previous experiences, this was not a surprise, even if it was a little frustrating on the night, and had been worked through in Delivery of Work in Possessions (DWWP) workshop sessions before the possession.

Taking 300 tonnes of spoil out meant something like 300 tonnes of new backfill had to go back in, all transported in bulk bags from a road-rail access point 200 metres east of the station. After that, the new spans went in without issues and the new platforms were landed on the cill beam upstands.

With the deck waterproofing pre-installed, the decks were handed to the pway team which made swift work of installing the track in time for signal testing and handback on time (with four hours to spare).

Along with the impressive list of materials and components used, it mustn’t be forgotten that substantial quantities of cake were consumed. It pays to give attention to the concerns of local residents, one of whom rewarded the workforce with an unending supply of cupcakes.

In the days following the possession, the platform surfacing, lighting and furniture were completed. So, too, were the final complex connections that fused the new construction with the last remaining elements of IK Brunel’s GWR cast-iron parapets.

After that, the temporary works were dismantled and the vista of the footbridge and the cast iron parapets has been restored to be everyone’s pride and joy once again.

This article was written by Grahame Taylor

Read more: Taking the Northern line to Battersea

 

Taking the Northern line to Battersea

On the roof of the Northern line extension’s Battersea Park Road base is a decked terrace which looks out over the expansive worksite that now surrounds Battersea Power Station. One only has to cast one’s eyes briefly around the site to get an idea of the well-tuned production line that’s required to excavate rail tunnels.

A large rectangular launch shaft sits directly below, surrounded by the precast concrete segments used to line the tunnels and the two cranes that are lifting them in. A conveyor system hangs off the side, transporting spoil from Helen and Amy, the two tunnel boring machines (TBMs) which are currently making their way towards Kennington station – an interchange station for the Charing Cross and Bank branches of the Northern line.

Following tunnelling tradition, both TBMs have been named; one after British astronaut Helen Sharman and the other after aviation pioneer Amy Johnson.

The 3.2km extension will include new stations at Battersea Power Station and Nine Elms. The latter is situated just down the road from the site of the former Nine Elms railway station. This had been a terminus station on the London & Southampton Railway during the brief 10-year period it was open between 1838 and 1848. Since then it has been the location of the L&SWR’s carriage and wagon works and a freight yard. Badly damaged by bombs during the Second World War, it was demolished in the 1960s and the flower section of New Covent Garden Market now stands in its place.

 

£1.2 billion project

Serious calls for an extension of the Northern line to Battersea were first made in 2007, but it wasn’t until 2014 that the project received government approval. Things moved considerably quicker after that and, later that same year, a joint venture between Ferrovial Agroman and Laing O’Rourke (FLO) was awarded the main construction contract.

The Greater London Authority will borrow up to £1 billion to fund the line’s construction, although the current cost quoted by Transport for London (TfL) is £1.2 billion. The funds to repay the loan will be recouped later on from the local developers set to benefit from the resulting surge in property prices.

The site around the iconic power station is substantial. To the left of the launch shaft is the Battersea station box, beyond that is the junction of the South London Line and Brighton main line. The huge regeneration project currently underway around Battersea, Vauxhall and Nine Elms – dubbed Dubai-on-Thames – will rely on the Northern line extension (NLE), and the TBMs are now operating 24 hours a day, seven days a week, to deliver it.

Articulation joints

During a tour of the worksite, Jonathan Cooper, the project manager overseeing the tunnelling phase, explained the progress that had been made following the launch of the TBMs in March this year. These machines, supplied by French manufacturer NFM Technologies from its factory in Le Creusot, are slightly smaller than those used for Crossrail’s tunnelling programme. However, NLE’s tunnels will still be wider than the existing Northern line tunnels to allow enough room to install an escape walkway.

From Battersea, the twin-bore tunnel will run beneath the Victoria line at Vauxhall and connect up to the Charing Cross branch of the Northern line at Kennington. Two permanent ventilation shafts will also be constructed at Kennington Park and Kennington Green.

As well as running close to the Victoria line, the NLE passes just a couple of metres below the South West Storm Relief Sewer, which is located between the two new stations. As part of the preparatory works for the route, Amey installed eight articulation joints along a 55-metre segment of the sewer to allow it to flex as the TBMs pass beneath.

Helen is now well on her way towards Kennington with Amy following on behind. Excavation of the station boxes at Battersea and Nine Elms is well advanced. Later this year, both TBMs will stop short of the Kennington loop and the final breakthrough will take place during a closure of the Northern line at Christmas.

Project manager Jonathan Cooper

Learning lessons from Crossrail

Tunnelling programmes are challenging engineering feats, particularly when historic records prove unreliable. In one case, a water well was discovered in the path of one of the TBMs, 10 metres away from where the plans showed it could be. In this kind of scenario, TfL and its contractors have to work quickly to get the tunnelling programme back on schedule and try to minimise any delays to the rest of the programme.

The London clay Helen and Amy are wrestling with is also very similar to the ground conditions that Crossrail’s engineers had to overcome. Indeed, Jonathan said the NLE project has looked to learn lessons from Crossrail.

Helen and Amy are served by six locomotives which help ferry people and equipment from the launch shaft into the tunnels. At any one time, each TBM will have around 15 operators loading concrete segments into the TBM and overseeing its progress.

The TBMs move at a rate of around 50mm a minute and install around 20 precast concrete rings a day – altogether 20,000 segments will make up the tunnel’s lining. Each tunnel ring is made up of five segments and a key; software used to control the TBM can work out what segment it needs next up to three rings in advance.

Credit: TfL.

300,000 tonnes of earth

One of the most important parts of the entire process is the conveyor system that removes spoil from the site. The earth that is excavated is mixed with water and a foaming agent to make it more malleable and easier to transport.

Barges rather than lorries are being used to move spoil from the site, and TfL estimates that around 300,000 tonnes of earth will be excavated during the tunnelling phase. TfL’s figures suggest that transporting the waste on the back of a truck would have added 40,000 lorry journeys to London’s congested road network. Instead, the spoil will leave site via the Thames where it is being taken to Goshems in Essex, to be used to create arable farmland on a former landfill site next to Tilbury power station – a site that was also used to dispose of some of the material excavated for Crossrail.

Credit: TfL.
Credit: TfL.

2020 and beyond

Both TBMs are due to complete their drives in the autumn, at which point they will be returned to the manufacturer and the fit-out of the tunnels will begin.

TfL plans to begin the station fit-out in 2019 and hopes to complete the extension by 2020.

The NLE is viewed by TfL as part of its ongoing upgrade of the Northern line, which has included retrofitting the line with CBTC signalling and upgrading stations including Tottenham Court Road, Bank and Camden Town.

Beyond 2020, there are those who would like to see the NLE taken all the way to Clapham Junction, connecting one of the country’s busiest stations to the London Underground network.

Although it hasn’t been ruled out, TfL has said a further extension wouldn’t be viable without Crossrail 2, which includes Clapham Junction on its proposed route map. A TfL consultation document for Crossrail 2 indicated that any further extension of the Northern line would rely on the project going ahead. Otherwise, the result could be even more congestion on Northern line services.

To give an idea of scale, Crossrail 2’s tunnels will be 10 times as long as NLE, which could well end up being the warm-up act for London’s next mega project.

This article was written by Marc Johnson

Read more: Manchester Metrolink: a world-class tram system

Atkins awarded £29m resignalling contract in Anglia

Network Rail has awarded Atkins a £29 million contract for the resignalling of the 42km route from Norwich, through Great Yarmouth, to Lowestoft.

Atkins will provide a full suite of GRIP Stage 5 to 8 design, engineering, construction, testing and commissioning services.

Mechanical interlockings will also be replaced by Alstom’s programmable ElectroLogIXS digital interlockings.

The resignalling works will see trackside infrastructure – such as cabling and relays – removed, with the new hardware monitored and controlled from a new digital control centre at Colchester Signalling Centre.

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The work will result in less equipment to maintain and better value for money in terms of the capital and operational costs for buying and running the system. The project is due for completion in spring 2019.

Atkins transportation programme direction Adam Parsons said: “Using a digital interlocking system deployed with our overall system architecture significantly reduces the amount of time which track engineers will be required to spend in safety-critical environments, maintaining and repairing signalling systems.”

Network Rail’s programme director for signalling Huw Edwards added: “This scheme will really benefit passengers by improving reliability on this line as part of our Railway Upgrade Plan.

“We’re also going to be improving safety on the railway by upgrading six level crossings and putting in technology to make the railway safer for all.”

Read more: Manchester Metrolink: a world-class tram system

 

Manchester Metrolink: a world-class tram system

Figures recently released by the Department for Transport (DfT) indicate that England’s tram networks have reported their highest passenger numbers and vehicle miles since records began. 267.7 million passenger journeys were recorded in 2016/17, which is an increase of 6.2 per cent on the previous year and, according to the DfT, the highest figure recorded.

In addition, since 2006/07, passenger journeys have increased by 49.9 per cent. Things are definitely looking up for tram systems across the country, with new extensions being built and planned on many of the networks that now exist.

One of the tram systems included in the DfT analysis was Manchester Metrolink. Transport for Greater Manchester (TfGM) has spent over £1.5 billion to expand and develop the network since 2008 when MPT, a joint venture of VolkerRail and Laing O’Rourke (MPact) in consortium with Thales, was awarded a design, construct and maintenance contract to deliver lines to Media City, South Manchester, East Manchester, Oldham and Rochdale, as well as a new depot facility at Trafford Bar.

The MPT consortium

The scope of the works is shared between the Laing O’Rourke/VolkerRail (MPact) JV, which is responsible for the design, construction and maintenance of the civil engineering and track, and Thales which takes care of all the electrical works. In addition, Thales has a contract direct with TfGM for the Tram Management System.

Whilst delivering this initial phase, MPT worked closely with TfGM, as owner of the Metrolink network and overseer of the expansion works, to define a scope for future lines. As a result, a second phase of extensions was awarded early in 2010, extending the South Manchester line to East Didsbury and the East Manchester line to Ashton, together with increasing the capacity of the Trafford Bar Depot.

Further extensions were awarded later in 2010, comprising a new line to Manchester Airport and town centre routes for Oldham and Rochdale.

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Ashton crossing.
Ashton crossing.

Second City Crossing

Following this, in 2014, the contract for the Second City Crossing was awarded to the MPT consortium. This represented a critical phase of the development of Metrolink following the successful completion and delivery of the 14.5km extension to the Manchester Airport line. In total, over 60km of new track and 57 new tram stops were completed across this rapidly expanding network.

The completion of this work would realise TfGM’s aspiration, which started back in 1982 when the metro link concept was first mooted, to create a “world class transport system” for the people of Greater Manchester.

A huge challenge

However, this phase of the programme was not going to be easy since it included removing a significant bottleneck in the centre of the city. It also involved working around listed buildings, cherished by Mancunians and English Heritage alike, and minimizing any disruption to the many high-profile businesses along the proposed corridor for the tram extension.

The length of the second city crossing is 1.3km, extending from Victoria railway station, down to Exchange Square and through St Peter’s Square, before joining the existing network at the Deansgate-Castlefield stop. Each location presented huge challenges for the engineers, particularly the section through St Peter’s Square.

Running down one side of St Peter’s Square are the Manchester Central Library and the Town Hall, both treasured listed buildings. In the middle of the square there was a Cenotaph and a stone cross, alongside an existing one-platform stop for the tram. The Square also acts as a thoroughfare for thousands of people every day.

The approach adopted by MPT was to agree a nine-week closure of the square in 2015, followed by a period of single line working using a simple wooden token system for tram operations, and then another nine week closure the following summer to complete the re-modelling.

One-team approach

Fortunately, the MPT consortium and TfGM had cultivated and developed a one-team approach which was proving to be very effective, thus enabling such a potentially disruptive arrangement to work efficiently and without conflict.

During the closures, new S&C layouts were installed at both ends of St Peter’s Square. The existing platform was demolished and two new platforms were constructed. Precast concrete units, each weighing 10 tonnes, were cast off-site and installed overnight using a tower crane that was working on an adjacent site. In addition, the elegantly designed platform canopies, fully equipped with cameras, public address systems, information screens and lighting, were constructed off-site. This ensured that work on site was kept to a minimum, leaving it uncluttered for the thousands of people who walk through the square each day.

Although the Cenotaph, built in 1924 and 12.8 metres high, was not a specific part of this project, it had to be moved to a new permanent position behind the Town Hall. It had been designed by Sir Edwin Lutyens, as had, amongst other fine buildings, the London Cenotaph and the Midland Railway War Memorial in Derby. His original drawings were used to dismantle the structure and reconstruct it – an approach preferred to jacking up the structure and moving it to the new site.

The stone cross was repositioned and a time capsule was also buried under the new flagged pedestrian area alongside the tracks.

Between St Peter’s Square and Exchange Square, on Cross Street, is a fairly modern building called the Cross Street Chapel. The new tram route runs down the centre of the road and, many years ago, there was a different chapel which had a graveyard that extended into the road and below the path of the tramway. Records suggested that there were probably about 123 people buried in the graveyard, so they all had to be carefully/respectfully moved as part of the project.

Archeologists were called in to oversee this sensitive operation and, when they started to carry out the excavation, they came across bodies that were stacked on top of each other, probably family members of all ages. The final count was 270 bodies, which were carefully exhumed and reburied elsewhere.

An aerial shot of the depot.
An aerial shot of the depot at Trafford Bar.

Ahead of schedule

The first phase of the Second City Crossing was finished in December 2015. The newly upgraded tram stop in St Peter’s Square was ready by August 2016, with the whole work becoming fully operational by early 2017, well ahead of schedule.

New additional depot facilities at Trafford Bar were completed, with increased stabling for the new M5000 tram fleet that had replaced the older T68 trams. The depot was constructed on a former industrial site, where buildings had to be demolished and the ground thoroughly investigated and treated. A new stabling area has been constructed alongside a maintenance building with a tram wash and sand plant plus six kilometres of ballasted track.

The integrated team has won a cluster of awards for its achievements, including the Light Rail Project of the Year Awards (over £50 million) for 2015 and 2016, as well as the 2015 National Rail Award for Civil Engineering Achievement of the Year and the Major Civil Engineering Project of the Year over £50 million at the 2015 British Construction Industry awards.

There are many more, but what of the future? What are the plans for this ever-expanding tram system?

In terms of the new Trafford Park line extension, valued at £350 million, preliminary work has already started and the plan is to complete it by 2020. Detailed BIM designs are well underway and underground utilities are being renewed, relocated or modified to improve access.

Careful planning, coordinated by the MPT utilities team, is arranging to share use of the traffic management and service trenches. It is definitely a complex programme of work.

Vegetation is being cleared and embankments extended. Land purchase is a key element in this phase, as TfGM is determined to ensure that this new extension will not deplete existing transport routes. This is particularly relevant given that the line will have a stop adjacent to Manchester United’s 75,000 capacity stadium.

The new line will follow a sharp curve alongside the ITV studios. Understandably, ITV, which is continually filming on its sets (including Coronation Street), has stipulated that vibration and noise are kept to a minimum, so there are some interesting challenges to address here. Close to the studios is the Imperial War museum, while the route ends at the rapidly developing Trafford Centre – all of which need to maintain their access.

There is little doubt that this extension will be much appreciated by the thousands of commuters who work in this fast-growing business area. It will also strengthen and underpin TfGM’s vision and aspiration to provide a public transport service that encourages people to leave their cars at home.

It is an aspiration that bodes well for the future of Manchester. A future in which Manchester Metrolink will feature prominently, thanks to the expertise and skills that the MPT consortium and its supply chain has developed over the last nine years, working together in this busy, bustling and growing environment.

This article was written by Collin Carr.

Read more: Waterloo and South West Route Upgrade

 

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