Track DST: Exploring Network Rail’s data mine

27th April 2018

Network Rail is the proud owner of a multitude of infrastructure databases – and, no doubt, many more in other disciplines too. They range from the whimsically named TiCled to the positively antediluvian GEOGIS. The former is the Tight Clearance database, the latter the complete record of track and its components which started life in the days of huge dot matrix printers and mountains of folding paper. To be fair, GEOGIS has now been consigned to history, replaced with the INM (Integrated Network Model).

Then there’s CARRS (Civils Asset Register And Reporting System) and TRUST (Train Running Under System TOPS -that’s the Total Operations Processing System) and RDMS (Rail Defect Management System) amongst a host of others.

They’re all really worthy in their own rights and have proved invaluable to those whose specialty relates directly to the database in question. In the joined up railway – the digital railway – there’s a problem for frontline engineers. To put it mildly, it’s not practical for those dealing with day-to-day decisions to start aligning all the databases to see where the critical influences occur. Because of history, because of technology, because of the original intent and use of the information, few of the databases are readily compatible.

Cyclic top isn't always visible. — Cyclic top isn’t always visible.

The Track DST

This is where the team building the Track Decision Support Tool – the Track DST – comes in. It is working within the ORBIS programme, which has the objective to “serve Network Rail and the GB rail industry as the trusted source of asset-related information and insight, from which informed decisions can be made to balance risk, performance and funding to best deliver Network Rail’s Promise”.

ORBIS – Offering Rail Better Information Systems. For a more comprehensive account of ORBIS, have a look at the May 2015 edition of the Rail Engineer or browse through our ‘In print’ archive on www.railengineer.uk, it’s in issue 127.

As Jonathan Schofield, communications manager for the ORBIS programme, explains, the overarching vision for the Track DST project is to develop decision-making capabilities that enable Network Rail to make evidence-based decisions for renewals and refurbishment, for predictive and preventative maintenance, and to improve effectiveness.

All of this means painstakingly boiling-down all the data sources and making them readable and intelligible. Victor Adeoye has that task and, thanks to his efforts and those of his colleagues, a comprehensive database containing a wealth of information is being built and refined.

Drilling down

At the moment, what is being constructed is a proof of concept. It is assembled on a weekly basis and so is not real time – although, ultimately, this could be the aim. The Track DST splits the railway into 220-yard lengths. To some this may look like one-eighth of a mile – which indeed it is. To others – those long in the tooth – it looks like 10 chains, suggesting that some of the databases are pretty old, predating full metrication by several decades. In fact, within these 220-yard lengths, it is possible to access much finer detail.

Drilling down, data mining, or whatever is the current term, is an accepted technique in the construction of any modern decision tool. But it is this feature that has taken a great deal of effort by the team bearing in mind where all the information has come from. Drilling down is now possible, and possible to an impressive extent.

The focus of the task is not only to see the history of a stretch of track in terms of work done and money spent, but also to use all that history to build a predictive tool so that future problems can be treated before they cause problems with speed restrictions or line availability.

The Track DST was originally built as a tool to assist in the management of switch and crossing assemblies, but it has now been expanded to include all issues relating to plain line. In the future, it may be further expanded to include features in what is traditionally known as ‘the permanent way’ – fencing, drainage, earthworks, structures and even signalling and electrification.

Presenting the most recent version of the tool, Martin Mason, information development manager, was able to show how it is possible to make reliable predictions of the development of serious track faults based on objective observations by the track recording coach. Future spends can be predicted, and thus decisions on whether to renew or maintain a stretch of track can be made.

Using the tool appears disarmingly simple which, in itself, is an indicator of the effort taken to integrate all the information sources.

The issue of Cyclic Top

In a recent development, some fascinating analysis has been carried out on the perplexing problem of cyclic top.

Perhaps it’s worth explaining cyclic top and why it is so important in the modern railway.

First of all, it’s important because it causes derailments – and major derailments at that. What is it? Basically, it’s a series of faults in ‘top’ – the quality of the longitudinal profile of the rail. Cyclic top faults are those that occur at regular and evenly spaced intervals. Of particular concern are those faults that typically occur every 4.5, 6, 9, 13.5 and 18 metres, but the precise interval can vary according to the prevailing rolling stock and speed.

Why are these faults a problem? Here it is worth looking at a bit of history. Fifty years or so ago, most freight wagons had short wheelbases – typically about ten feet. They were particularly prone to derail at track twist faults, where one rail changes its relative elevation to the other rail at a gradient of 1 in 240 or worse. The wagons could not tolerate this severity of twist and would easily flange climb and fall off. Speed was – by and large – not relevant. Twist faults can be seen on inspection and, most importantly, they can be measured with a simple crosslevel gauge. In this way, ground level staff were able to identify and control problem sites.

The derailments of short wheelbase wagons died out when the use of these wagons ceased. But other strange types of derailment started to occur. These involved longer wheelbase wagons at sites that appeared to have track with no twist fault exceedances.

When the derailment sites were surveyed, it was found that top faults occurred at regular intervals and it was soon established that the problem involved not only the track, but also the suspension characteristics of the vehicles along with speed. Cyclic top had been discovered, but this was little comfort to those at ground level who had no means of measuring the sites and no access to the early computer programmes that simulated the behaviour of particular types of wagon.

Although today there are test trains that can identify cyclic top and give a measure of risk associated with each one, it is still a difficult issue to manage between train runs.

A breakthrough

The recent development in the Track DST can be termed a breakthrough in infrastructure management. Team member and network data manager Andrew Nwichi-Holdsworth, who started on the railway as a trackman in the Shipley Kango gang in 1979, has been analysing a number of sites. He has applied a selection of filters to get rid of the ‘noise’ and to reveal cycles at different wavelengths of top fault.

This analysis shows that, far from occurring at only a few locations, critical wavelengths are almost everywhere. It is as if the whole of the railway has been affected by the resonance of vehicle suspension. The top faults are largely benign, but they can grow to serious proportions when vehicles encounter a trigger point. This can be something like a wet bay, a dipped joint, a bridge-end or a level crossing. Derailments happen when wagons start to bounce and roll and yaw – all triggered by these regular top faults which Andrew’s analysis clearly shows are developing to critical levels.

He can also show how these faults grow from one recording to the next and so this is the start of a predictive tool that can prompt the remedial action needed to prevent a disruptive fault. There are, of course, further issues in that the longitudinal stiffness of track has to be understood so that preventative action has a beneficial effect rather than making things worse in the long term.

One mile worth data at the 13m wavelength. As can be seen, there are several cycles where the amplitude to the wave crosses the threshold of 4.5mm at around 35m0825yds, indicating a cyclic top event (three or more peaks). The middle chart shows potential precursors (wet beds) to this cyclic top event.

Exports

The team is busy, not only refining the Track DST, but also presenting its findings to those charged with the responsibility of maintaining assets on the ground.

These audiences now include railways from outside of the UK. Problems with asset management exist all over the world and cyclic top, for one, is no exception. Heavy-haul freight railways are realising that they need to get a grip on this problem, especially when there are limited time windows available to intervene.

The ride characteristics of wagons on other railways will differ from those in the UK, but this can be overcome by applying different filters to the data so as to isolate different wavelengths. The tool can be applied worldwide if needed, a sign of the UK railway industry asserting itself again as a world leader.

At the start of the digital railway programme, the founding minds were at pains to stress that the real benefits from coordinating all the asset data would really kick in some five or so years down the line. It is now five years on… and the predictions are coming true.

A report of Network Rail’s successful engineering works at Easter

27th April 2018

In its review of the work on the railway infrastructure over Christmas and the New Year, Rail Engineer reported (issue 160, February 2018) that 32,000 people worked at 3,000 sites to deliver £160 million of work. The work also brought about the usual crop of sensationalist headlines in the national and regional press. As early as October the Daily Star was predicting “Christmas CHAOS” – in capitals – while the Sun predicted that “Rail passengers face ‘worst ever’ Christmas delays”.

In London, the Standard said that the capital was “Braced for chaos” and the Birmingham Mail said that “Railway works could spell train chaos”.

The Oxford Mail at least tried a different approach. “No Silent Night – ‘Noisy railway work could ruin Christmas’ in Oxford” was its headline on 10 November.

It was all very familiar, and largely ill founded as plans went off without too many problems, replacement bus services were in place and, when commuters returned to work after the holidays, their trains ran to timetable.

Move forward to Easter and it was all very different. A Google search using similar terms failed to bring up any major headlines, the first being the Richmond and Twickenham Times which simply stated that “Major engineering works are planned for South Western Railway over the Easter holidays”.

Why was the situation so different? Were no major works planned for the Easter holiday weekend?

In fact, they were. Although only half of the number of workers were mobilised – 15,800 this time – they were still active on 3,000 worksites and delivered £118 million worth of engineering work.

20 projects were identified as RED through the Delivering Work Within Possessions (DWWP) standard, therefore carrying a greater risk of overrun and/or a more significant impact in the event of an overrun, down from 40 at Christmas. These included Bristol Area Resignalling works, track lowering works at Cheetham Hill as part of the North West Electrification programme (NWEP), alongside a number of significant track, maintenance and structure renewals across the country.

On this occasion, the holiday period was a brilliant success, with no attributed delay minutes despite the large portfolio of engineering works as every one was handed back on time (at Christmas only 98.6 per cent were). And while nine injuries were reported, they were all minor in nature and no time was lost as a result.

So what work was carried out in such a successful Easter programme? For a change, let’s look at it from North to South.

Shotts electrification

Electrifying the line between Holytown junction and Midcalder junction will provide an additional electrified route between Edinburgh and Glasgow.

Easter also saw the start of a ten-day blockade on the Shotts line for electrification work and a £3.5 million transformation of Livingston South station that includes widening and extending its platforms.

Over Easter, OLE equipment was installed in the Midcalder junction area. The wire runs in the junction were energised and section proving completed, but the lines will remain blocked to electric traction until full energisation of the route takes place in October 2018.

Polmadie and Rutherglen renewals

The Polmadie and Rutherglen Signalling Renewals (PARR) project involves the renewal or refurbishment of signalling and telecoms equipment in the WSSC Polmadie workstation control area, the renewal of S&C units at Rutherglen East, West and Central junctions, and the remodelling of the electrification system to align with the new track configuration.

The Easter disruptive works were a critical stage in the lead up to the commissioning of the new OLE layout. There was also follow up welding, stressing and tamping from track stage 1 renewal of plain line and new 980 points.

Motherwell North signalling renewal

To renew life expired signalling assets & relay based interlockings and relocate the signalling control from Motherwell Signalling Centre to the West of Scotland Signalling Centre (WSSC). This includes new lineside signals, telephones & cables, troughing, location cases, Westlock and WestCAD.

The Easter disruptive works were the second of three separate ‘Workstation’ phases: Newton (commissioned April 2017), Whifflet (Easter 2018) and Motherwell (August 2018). All of the works were completed as planned and included the closure of Motherwell Signalling Centre panels 2 and 3 and transfer of control to Whifflet Workstation in the West of Scotland
Signalling Centre and the commissioning of new interlockings and trackside equipment.

Polmadie workstation and Yoker East workstation fringe were handed back on Saturday morning and Edinburgh Cowlairs workstation fringe on Sunday morning.

Larkfield S&C reballast

A 76-hour possession was required to reballast two sets of points between Glasgow Central and Carstairs on the West Coast main line.

The S&C panels were disc cut and then removed using PEM self-propelled laying and renewal gantries. After excavation and the application of new stone, the panels were relayed and the track dressed, welded, stressed and tamped. The Up Clydsdale line reopened at its 40mph line speed while the Down road had a TSR imposed of 50mph.

Preston station stressing

Delivered by the works delivery unit, track stressing works in Preston station were part of the ongoing Preston to Blackpool North line upgrade. This involved rebuilding 11 bridges, remodelling 11 station platforms, replacing 11km of track, upgrading drainage and installing 84 new signals.

Only the station stressing works were classified as Red, as they could have caused operational problems on the West Coast main line if they hadn’t been handed back on time after Easter. The Blackpool line was actually closed, so those works weren’t classified.

As it happened, the opening of the line was put back three weeks due to weather conditions including ‘the Beast from the East’ and the breakdown of critical machinery. The line finally reopened on Monday 16 April.

Cheetham Hill

As part of the NWEP Phase 5 electrification, the Up and Down Rochdale Fast lines (Platforms 5 and 6 Manchester Victoria) were lowered under Cheetham Hill road bridge during a 100-hour possession to allow for the future installation of overhead line equipment (OLE). This was the final piece of advanced civils works for NWEP Phase 5, which will allow for journey time improvements between Manchester Victoria and Stalybridge.

A total of 200 metres of track was lowered, 2,300 tonnes of spoil removed and 1,920 tonnes of new ballast installed, along with additional work. Buried services and obstructions were encountered during excavation, which therefore took longer than had been anticipated. However, this was managed within the programme.

Halton Curve

The Halton Curve connects the Chester to Warrington line at Frodsham Junction with the Liverpool Crewe line at Halton Junction. During the four-day Easter blockade, works were undertaken to install a new crossover and renew the turnout at Halton Junction. This will enable bi-directional train movements on the Halton Curve, as a similar new crossover was installed at Frodsham Junction back in November 2017. The completion of the overall project in May 2018 will support the introduction of a new direct passenger service between Liverpool and Chester via this curve.

A progressive assurance check was used to enable 90mph line speed handback on the Up main – this was a first for the S&C North Alliance Crewe depot. Once tested, the points were secured out of use, ready to be commissioned by the Weaver Wavertree project during the early May Bank Holiday.

Excavation of the Down Main exposed an unidentified water mains pipe with hairline fractures. United Utilities was contacted to provide support with the repair of the damaged pipework.

Bristol Area Signalling Renewals and Enhancements

The BASRE project is part of the Western Mainline Signalling Renewals programme, which is an enabling project for the Great Western Mainline Electrification Scheme. BASRE will introduce AC-immune signalling equipment and re-lock and re-control to Thames Valley Signalling Centre (TVSC).

Stage 4 was the largest stage, as it included Bristol Temple Meads station and the complex junctions and depots within the commissioning footprint. It was the largest signalling commissioning undertaken by Network Rail, involving over 2,240 people over the 123-hour commissioning period, and introduced:

355 SEUs (signal equivalent units);
146 signals;
130 point ends;
184 location cases
Five new REBs (relocatable equipment buildings);
Four new power supply points;
Over a quarter of a million metres of new cable;
All controlled from a new desk at Thames Valley Signalling Centre, Didcot (TVSC).

Canonbury Up plain line

The single-track freight-only Canonbury Curve runs alongside Emirates Stadium and through Canonbury tunnel, connecting the North London line with the East Coast main line at Finsbury Park. Over Easter 2018, IP Track replaced 106 metres of track and a total of 588 metres of steel sleepers.

During a 52-hour possession, different methods of working were used due to the awkward location. In one section, the old rails were burned into six-metre lengths and lifted out, with new rails being installed using McCulloch handling machines. In another, panels were cut out and removed by a Kirow train, the ballast was excavated and replaced using RRVs and a bulldozer, and new track was laid using an NTC (new track construction) machine.

All planned works were completed and the possession handed back to operational traffic on time at the published handback speed of 20mph TSR. A post-handback issue with a signal fault was rectified and caused no delays to operational traffic.

Gidea Park S&C renewal

Between Gidea Park and Harold Wood stations, IP Track replaced seven point ends and four fixed diamonds in a like-for-like renewal, along with 343 metres of plain line track in a 98-hour possession.

The programme was split into two stages – the Down Main and Up Electric formed Stage 1 and the Down Electric was classified as Stage 2. Existing track was scrapped out, excavated and new base stone dropped prior to relaying. New panels were installed using two Kirow cranes, after which top ballast was applied using auto-hoppers before two Matisa tampers prepared the track for a hand back with a 50mph TSR.

Great Eastern OLE renewals

This long-running project is replacing the fixed termination OLE from Liverpool Street to Chelmsford with a modern, high-reliability auto-tensioned system. When complete, the project will have installed a total of 345 new OLE wire runs, including new support structures and associated registration assemblies.

Three wire runs were installed over Easter, one through Ilford station, one on Ilford flyover and one on the Up Electric to Down Electric crossover, totalling 4.26km. This has created a continuous 39km section of auto-tensioned OLE between Ilford and Chelmsford.

Kensal Green plain line

This renewal was on the Fast lines between Camden and Wembley on the West Coast main line – with the majority of the renewal site within Kensal Green tunnel.

The possession was planned for 78 hours and a total of 620 metres of the Down Fast Outside line was to have been removed and excavated, then replaced after a geotextile had first been laid.

Due to significant water table flooding issues, worsened by the rain, the engineering decision was made that the depth of the dig was reduced over 80 metres of the site and the sand installation was curtailed. Despite these issues, the full length of the site was renewed and handed back on time at 60mph, as opposed to the published 50mph TSR, due to quality of the installation.

New Cross Gate to Brockley

Working in a platform, with tight clearances in some areas, a 51-hour possession was required to replace some 800 metres of track on this busy commuter route into London.

Once the conductor rail had been removed, the track was removed and replaced by conventional means using a mobile flash butt welder. An RRV failed as it was leaving the site, causing the possession to be handed back 20 minutes late. However, no operational traffic was delayed, and the site was actually cleared for a handback at 60mph linespeed instead of the 50mph TSR that had been anticipated.

Fairfield underline bridge replacement

Fairfield bridge is a single span wrought iron underline bridge located four miles 1529 yards from the country end of Wandsworth Town station. Consisting of simply supported wrought-iron girders supporting rail timbers, the structure was in poor condition and deemed life expired.

The bridge deck replacement was delivered by One Team Wessex, a Network Rail and Osborne collaboration. A total of 45 operatives worked within the replacement possession, which totalled approximately 2,250 man-hours.

The existing bridge deck was replaced with four new, single span, U-type decks (steel main girders with composite floor), founded on new precast concrete cill beams. The bridge was renewed by a 45-strong team during a 99-hour possession through the use of one 750-tonne mobile land crane, one engineering train, one tamper, three RRVs and four mini-diggers.

The four newly installed tracks were reinstated on ballast and then tamped.
Lines were opened to traffic under planned 50mph TSRs on the morning of 3 April. The site team was able to complete additional track welds that were originally planned for a follow-up possession whilst handing back three and a half hours early. This helped to de-risk future stressing and welding works which allowed the line to be brought up to a full line speed of 60mph on 9 April 2018 (week 2).

Victoria Phase 2b, Sutton and Wimbledon

The Victoria Phase 2b project was initiated to re-lock and re-control the existing life-expired interlockings at Sutton and Wimbledon and renew all lineside signalling assets in the Sutton area. During a 99hr possession, the project successfully re-controlled the new signalling from Victoria ASC to Three Bridges ROC, removed redundant signalling assets, brought into use new signalling equipment and carried out the change over from track circuits to axle counters in the Sutton Interlocking Area.

In total, 70 new signals and 102 signal equipment cases were brought into use. Recovery of the redundant equipment was delayed by heavy rain and strong winds, so that work had to be rescheduled to maintain the final handover time. A hand trolley derailed and had to be recovered, although no damage was caused.

Post commissioning, three separate equipment-related issues have resulted in passenger service delays. These have been addressed and investigations are ongoing to understand the root cause.

Sevenoaks tunnel

And finally, or most southerly, work continued in Sevenoaks tunnel. Built in the 1860s, the Victorian tunnel is one of the longest main line tunnels in Britain. Water has been a major issue since construction, causing track, signalling and power supply to deteriorate quickly, leading to faults, delays and sometimes speed restrictions.

Reported in Rail Engineer after Christmas (issue 160, February 2018), the work is being undertaken in stages over several holiday closures to replace blocked sections of tunnel drainage on a critical section of the route. Over Easter, the team overachieved, replacing more drainage in the central six-foot than had been anticipated.

Lasting legacy

Closing sections of the railway is never popular, but is essential as Network rail strives to modernise the railway and make it more reliable for years to come. Doing this in holiday periods reduces the impact on commuters, but it does disrupt travel plans by families who are trying to get together. As there seems little chance of a suitable alternative being found, rail closures will probably continue to be a feature of national holidays for some time to come.

However, the difficulties faced by passengers is well recognised. Martin Frobisher, route managing director for the London North Western route at Network Rail, said: “There is never a good time to carry out work that affects services but we worked closely with the train operators for it to cause the least amount of disruption.”

Meliha Duymaz, Network Rail’s route managing director for Anglia, echoed this sentiment: “Our engineers successfully carried out crucial upgrades over Easter which will significantly improve journeys. This work is important to support the growth in passenger numbers and to improve reliability as part of our Railway Upgrade Plan. I’d like to thank passengers for their patience while we carried out this work.”

So that was Easter. Next up – May Day!

Issue 163 – Incentivising Innovation

27th April 2018

What’s not to like about a DMU gearbox that offers savings in fuel, CO2 and diesel emissions, as well as reduced maintenance costs, so that it can pay for itself in about four years? The answer seems to be that the individual companies concerned do not get the full benefit from these savings and so are not incentivised to replace the current gearboxes.

As we describe this month, this problem was mentioned at the excellent Railway Industry Association’s innovation conference, at which delegates considered procurement and risk aversion to be significant barriers to innovation.

Yet much is being done to support innovation, as was shown at the RIA conference. This includes the way that work package owners are supporting the delivery of the Rail Technical Strategy requirements and various Network Rail initiatives including its revamped product approval process and its rail innovation and development centres.

The recent establishment of the UK Rail Research and Innovation Network (UKRRIN) was also described at the conference. This is a collaboration between academia and industry to provide purpose-built centres of excellence to develop new products and technology, for which private rail companies have committed investments totalling £64 million.

Despite this, there is sometimes not the incentive to innovate as with the gearbox example. This can be a problem with train operating franchises that do not last long enough to recoup their investment or innovations that cross the track-train interface. As our conference article describes, this is not such a problem in the electrical supply industry, in which the regulatory system actively encourages innovation.

Thus, it would seem that the ORR and DfT need to consider how a similar regulatory framework to incentivise innovation could be developed for the current rail industry structure.

Undoubtedly, future innovations will require the huge increase in telecommunications data capacity that could be provided by a 5G rail network. Clive Kessell reports from a recent telecommunications industry seminar that considered the mobile operators and equipment provider’s viewpoints, as well as wider business trends, to see what a 5G rollout will entail.

We also have a report from an IMechE conference that considered how to get more capacity and better performance from the current network. In her report, Rebeka Sellick explains the solutions presented at the conference and highlights the work done by the professional institutions to influence Government policy.

One factor reducing rail capacity is that signal spacing must allow for worst-case braking from poor adhesion. This happens when the small contact area between the wheels and the rail, the size of a one penny piece, cannot transmit the huge traction and braking forces involved. RSSB has led tests of additional and variable discharge sanders to find a solution to this problem. Malcolm Dobell explains why this is the biggest advance in adhesion management for years.

Extra capacity was also provided by some of the work undertaken during the Easter holidays. As Nigel Wordsworth reports, 15,800 workers on 3,000 worksites delivered work worth £118 million, all of which was handed back on time. Inevitably, such work affects train services over the holiday period, highlighting the importance of Network Rail working with train operators to minimise the disruption.

Deciding when track must be renewed, or when remedial action is needed, is a complex balance of risk, performance and funding. To support such decisions, Network Rail has developed its Track Decision Support Tool. As Grahame Taylor explains, this brings together data in the company’s various infrastructure databases, presenting it in an intelligible manner to better inform decisions. In addition, the tool will also predict the development of serious track faults.

The three-span 279-metre bridge over the Runcorn Gap is, as Stuart Marsh describes, a stupendous structure that is in need of extensive work, including steelwork and castiron parapet repairs, grit blasting and painting. In his article, Stuart explains how this work required bespoke solutions to take account of wind, tide, passing ships, environmental constraints and tight operational clearances.

A bespoke scaffolding solution was required for the brickwork repairs to Kilsby tunnel’s 20-yard diameter ventilation shafts. Graeme Bickerdike explains the intricacies of its erection and how the tunnel’s extrawide shafts were required to assuage the predictions of doom-mongers that it would be impossible to breathe in newfangled railway tunnels.

Today’s doom-mongers are concerned about the impact HS2 will have on the environment. Yet, as Lesley Brown has been finding out, the project’s sustainable approach will deliver an improved ecological outcome and its BREEAM certification gives an independent assurance that sustainability is in HS2’s DNA.

Some feel that HS2 is not required as hyperloop is just around the corner. Gareth Dennis debunks this myth in an article explaining why it is not a credible transport system despite its impressive engineering. Instead, hyperloop is an experiment, largely funded by Silicon Valley billionaires, which generates potentially harmful glossy publicity claiming that railways are an outdated mode of transport.

Whilst this may beguile those who do not look beyond the hype, the reality is that steel-wheel rail will continue to benefit the world for many years to come.