Guest writer: Simon Meades, Ecolite product manager at Taylor Construction Plant.
With the announcement this year that the UK has become the first major economy in the world to pass laws to end its contribution to global warming by 2050, the pressure is now on to bring all greenhouse gas emissions to net zero. This means good practice of energy management on site. Consequently, the efficient use of construction plant equipment powered by sustainable fuel has never been so important.
This creates a huge opportunity for plant hire companies to
expand their fleet and offer customers cleaner air products and services. It
also opens the market for new, innovative plant equipment that produces zero
harmful emissions.
There are many solutions already available, some of which
are currently being used or trialled by the rail construction industry, but
which ones are best is still to be proven. Working off-grid is perhaps the
biggest challenge, as connecting to the National Grid could dramatically reduce
CO2 emissions, instead of using diesel generators, which produce not only air
pollution but also noise.
Typically, nearly everything on site is run by generators – from light towers, CCTV, welfare cabins and power tools – so imagine the reduction in pollution if everything could be run by an alternative power source in the absence of mains electricity. Hybrid generators are one option, as they use battery and solar power to reduce the run time of the generator; diesel is only used to supplement the battery for high-power jobs or to charge the batteries.
The clean alternative
Another option is a hydrogen fuel cell/battery hybrid generator, which is completely free of diesel.
A hydrogen fuel cell generator produces electric power by
combining hydrogen with atmospheric oxygen. The only emission from these cells
is water vapour, and they are virtually silent in operation, which is a big
advantage when complying with Section 61 of the Control of Pollution Act. With
zero impact on air pollution levels at point of delivery, zero noise pollution
and no risk of fuel spill, hydrogen fuel-cell power arguably presents the
perfect solution for a healthier work environment.
This could be why we are increasingly seeing hydrogen fuel
cells in our cities. London now boasts entirely hydrogen-powered bus routes,
and many cities and motorways are installing the vital fuelling stations needed
to allow wider adoption of hydrogen vehicles. Britain also has its first
hydrogen fuel cell train, the ‘HydroFLEX’, being developed by Birmingham
University and Porterbrook, which presents a much greener solution than bi-mode
trains which run off electricity where there are overhead cables, and off
diesel the rest of the time.
Hydrogen fuel cells offer greater efficiency as, with a
continuous supply of hydrogen, a fuel cell can provide electrical energy
indefinitely, unlike a battery which requires charging or replacing. It is also
more reliable than trying to use sun or wind to generate a constant flow of
energy. However, hydrogen fuel cells can be hybridised with these renewable
energies to further improve efficiencies – making this technology very
versatile. For example, a hydrogen fuel generator with battery power and PV
(photovoltaic) solar panels can effectively provide sufficient energy to power
a welfare cabin.
So, when it comes to reducing carbon emissions for railway
construction and maintenance, hydrogen fuel cell/battery generators could help
provide a sustainable solution for reaching net zero. This technology is
already being used by several major rail infrastructure companies with great
success, not only to reduce carbon emissions but also to cut noise pollution
when working near residential properties.
Low noise, low pollution
A good example of this was the railway enhancement work
which took place in the Oxford area last year. Working 24/7, and in close
proximity to residential properties, the Network Rail Western Enhancement
Delivery (WED) team knew it had to make every effort to keep noise down to a
minimum.
It was therefore recommended that Network Rail needed the
TCP Ecolite TH200, which would give them a 200W LED output and longer run
times. This hydrogen fuel cell light tower, which is virtually silent in
operation, would also help WED to reduce noise pollution within the residential
area whilst work was being carried out at night over a five-week period.
TCP and Torrent Trackside provided Network Rail with 25
portable Ecolite TH200 hydrogen fuel cell light towers, which were positioned
at various site locations along the Oxford corridor. Collectively, the units,
which have been designed to carry four cylinders of hydrogen gas, delivered an
average of seven hours of LED light each working night over a five-week period.
During the project, 122 cylinders of hydrogen gas were used,
providing a total energy saving of over 19,000kWh and a significant reduction
of CO2, when compared to a modern diesel light-tower. The lights not only
reduced disturbance to residents, but also reduced the carbon footprint
throughout these intensive works.
Having equipment that is fuel efficient helps reduce vehicle
movements, which again contributes to lowering the carbon footprint, as does
having smart remote monitoring to control the run time of products during
periods of peak and low activity.
This is undoubtedly an exciting time for manufacturers of
plant equipment as the demand for zero-emission decarbonising products can only
increase if we are to reach net zero by 2050.
London Underground’s Northern line extension, which is being
built from Kennington to Battersea with a new intermediate station at Nine
Elms, uses Building Information Modelling (BIM) as the basis of its design and
documentation. This requires LU to put the same level of rigour and governance
into creating and managing information about infrastructure assets, as it does
in building and operating the assets themselves.
BIM is a process involving the collaborative production, use and management of digital representations of the physical and functional characteristics of a facility or asset. The resulting information models, when fully coordinated, provide a shared knowledge resource to support decision-making about a facility or asset throughout its life – from early concept stages, through increasing detailed design, construction, operation and maintenance, and ultimately decommissioning, removal and demolition.
The objective of BIM is to procure/produce, manage and
maintain data and information about engineered assets that are complete,
consistent and trustworthy for use across operational and business intelligence
purposes. This aims to drive efficiencies in the production, modification,
operation and decommissioning of engineered assets, through data analysis that
helps improve decision making to deliver best value to stakeholders.
BIM is a collaborative process that leads to better solutions for clients and their supply chains by enabling lean, accurate and complete design information for an effective construction process and leaves clients with better tools for asset management. Assurance is at the heart of BIM and, arguably, its most important use.
Telecoms and BIM
As part of its work on the Northern line extension, telecommunications systems integration specialist ADComms, a Panasonic company, has been implementing BIM within the business through both the design and construction phases and is working towards Level 2 BIM compliance. This will ensure that the company creates and shares appropriate information, in a suitable format, at the right time to facilitate better decisions throughout the delivery and operation of a built asset.
ADComms is currently committed to updating its current ISO
9001 suite of quality management documentation to incorporate BIM for
integrated project delivery design, CDM, safety planning, and assurance.
On the Northern line extension, this will contribute to LU’s
duty to deliver design, construction and maintenance/operations handover information
(both graphical and non-graphical), in line with the April 2016 mandate from
Government that all UK public infrastructure projects meet BIM maturity Level
2.
Carl Pocknell, ADComms managing director, commented: “BIM is
not the future, it is now – a day-to-day reality. With the advances in
communications technology being developed under Industry 4.0, this is an
opportunity to engage and develop holistic, collaborative, digital approaches
and methodology workflows and realise tangible benefits for our clients and
their end users.
“Once BIM adoption has been agreed, then BIM must become the
norm.”
When Abellio secured the ScotRail franchise in 2015, it soon commenced an exciting transformation programme to improve passenger services across Scotland’s network. Plans included a £475 million investment in new and better trains on routes between Scotland’s seven cities. These faster and more-spacious trains, with more carriages and new onboard facilities, will speed up journeys across the network, increasing capacity and enabling revised timetables that improve connections between services.
To support its new fleet, Abellio ScotRail is delivering a
programme of enhancements throughout its depot facilities, including at the
high-speed train (HST) depot in Inverness. This site required increased siding
capacity to accommodate the longer, five-car HST fleet and a range of
enhancements to improve safety and accessibility for drivers and maintenance
teams.
Longer trains
Abellio ScotRail appointed Stobart Rail and Civils to
construct the £1.5 million Inverness depot HST upgrade, ready for the arrival
of their new fleet. Stobart’s regional manager for Scotland, Keith Robertson,
said: “ScotRail’s investment in new trains will deliver great benefits for
Scotland, so we’re proud that Stobart can play a key part in creating these
vital depot facilities that will ensure each train performs at its best. We
have just finished an £11 million programme delivering track maintenance across
300 route miles in Scotland, so this was an ideal opportunity to further
contribute to great passenger experience.”
Track works at Inverness included the complete renewal of
three sidings to a new layout and longer length, together with installing two
new S&C units – one BV8 and one CV9.25 – that join the sidings and connect
them back to the main line.
Unusually, the project’s track design used vertical rails
throughout the plain line in the sidings rather than standard inclined rails.
This posed a unique challenge for Stobart’s procurement teams who quickly
realised there were no vertical baseplates available anywhere in the UK.
Using some impressive detective work, the team discovered
several projects in Germany that used vertical rails and they even found the
baseplate manufacturer who had supplied these schemes. Unfortunately, they had
no baseplates in stock and no plans to cast any new ones. Undaunted, Stobart
negotiated to acquire the baseplate moulds and bring them back to the UK, then
worked with a local supplier to cast the nearly two thousand new baseplates
that the sidings needed. They also produced a healthy supply of spares to
future-proof any maintenance needs.
The sidings’ alterations involved removing the existing and
relaying roads 6, 7 and 8 together with installing the two new turnouts. This
provided the ideal opportunity for Stobart to deploy its specialist road rail
fleet that includes laser dozers to grade the bottom ballast, Colmar heavy
lifters to position the S&C components and the new road-deliverable S&C
tamper to deliver a perfect track alignment. With the track reconfigured and
buffers installed, Stobart completed the extensive signalling modifications
needed to suit the new layout.
Within a depot environment, the major challenge is
invariably delivering the works programme alongside normal depot operations
without causing disruption that might affect vital maintenance work. At
Inverness, this was a particular challenge owing to the depot’s 24-hour
operations, with the depot servicing and maintaining the Highland Sleeper train
through the day and the standard fleet overnight.
Keith Robertson said: “Ensuring normal depot operations
continued unhindered was one of our key project objectives. We operate
logistics sites with a rail interface throughout the UK, so we understand how important
it is to minimise disruption.
“We worked together with the depot team to plan our works and ensure we segregated our activities from the depot’s operations. Daily coordination meetings then ensured that all stakeholders remained fully informed of upcoming works. This was a very successful approach, particularly when the depot’s maintenance programme often changed owing to emerging needs.”
Enhanced facilities
To improve access to the sidings for the drivers and maintenance staff, Stobart delivered an extensive civils upgrade that included new concrete driver-walkways alongside each siding. A new tarmac-surfaced depot access road and pedestrian crossings over the tracks ensured that the maintenance teams could safely access the new sidings.
Mechanical and electrical installations included shore
supplies positioned next to the buffer stops on each siding, along with nearly
150 low-level bollard lights to illuminate the siding walkways that would
otherwise be in shadow once a train is stabled next to them. These were all
served using a network of multi-way ducts that safely protect the cables below
ground and provide ample cable capacity for any future development needs.
Finally, an existing portal-framed shed spanned the existing
road 5 within the depot to protect the maintenance teams from the weather. To
enable safe maintenance of the HSTs in this shed, Stobart installed a new
exhaust ventilation system that positioned a series of extraction hoods
directly above the HST’s engine exhausts.
The successful completion of Abellio ScotRail’s HST depot
earlier this year marks an important milestone in its investment programme and
is another example of Stobart’s team in Scotland making a positive contribution
to the ongoing improvement of Scotland’s railway.
Chairman’s address to the IMechE Railway Division 2019
Graham Neil CEng FIMechE FIET is the 51st chairman of the
IMechE Railway division, taking over from 2018/19 chairman Andy Mellors. Almost
his first official duty was to give his chairman’s address, which he duly did
at the Institution’s headquarters in London on 9 September 2019.
It is traditional for new Railway Division chairmen to talk
about their careers. Partly, this illustrates the diversity of paths to senior
roles and, partly, it provides the authority for them to talk about the future
and challenges they hope to tackle.
Graham has worked for Transport for London (TfL) and its
predecessors since 1971 – a mere 48 years. He started as an indentured
electrical apprentice in the apprentice training centre at Acton Works, passing
a plaque with words to the effect that anyone starting an apprenticeship could
aspire to become the chief mechanical engineer.
That post was abolished long ago but Graham became
professional head of rolling stock for London Undergound in 2004, the nearest
contemporary role. He was appointed professional head of vehicles for TfL in
2018, which added to his portfolio vehicles from London Overground, TFL Rail,
London Trams, DLR, London Buses, Dial-a-ride Taxis, the Emirates Airline,
Bicycles, River Boat Services and the Woolwich ferries!
He has achieved this position over five decades, so summarising 48 years into a few words is not easy, but taking each decade in turn:
1970s – Graham’s 4-year apprenticeship included fabricating his own tools, and his first proper job involved repairs of unreliable electronic train components. Those of us of a certain age recall 1970s electronics and are glad reliability has dramatically improved.
1980s – Graham was promoted to the design department and became involved with specifying many of the electronic systems for the 1983 tube stock and 1986 tube stock prototype trains, including the very earliest electronic train control systems, the embryo of the Train Control and Management Systems of today.
He inflicted the first automated public address system on
unsuspecting customers. It was nicknamed Sonya as in “get ‘S on ya’ nerves”.
More seriously, Graham represented LU on a joint British
Rail/LU/Railway Industry Association initiative to produce standards and
specifications for train electronics to overcome the unenviable reputation they
had for reliability. These standards were the forerunners of today’s Euronorms
and ISO standards.
He was also nicknamed “Mr ATO” for his work developing a
replacement for the original, obsolete Victoria Line ATO controllers.
A further promotion saw Graham leading the rolling stock
electronics development section, where he was able to set up facilities to test
and evaluate equipment designed to comply with the new electronic standards.
1990s – With a reorganisation and with his experience of creating standards, Graham led a team creating and or updating standards for all LU rolling stock sub systems and critical components. This was followed by becoming effectively the internal Independent Competent Person for acceptance of new rolling stock at a time when privatisation of the main line railways had led to the acceptance and authorisation regulations becoming more formal.
He also led the work to improve understanding of the risk
from, and protection against, arcing in DC power circuits caused by double pole
earth faults on LU’s 600V floating-earth traction supply system.
Following yet another reorganisation, Graham was put in
charge of a team of about 25 rolling stock engineers supporting the Central,
Northern and Victoria line fleets as well as a small team of noise and
vibration engineers and a team that routinely surveyed the track at line speed,
capturing still images from passenger trains at a frame rate of 25 pictures per
second.
Later he was appointed as project engineer for the 1995 tube
stock Northern line trains being produced and brought into service by a Public
Finance Initiative contract that was, at the time, ground-breaking.
2000s – The Public-Private Partnership preparations led to the overwhelming majority of LU’s engineers being distributed amongst the “shadow” companies that would be taken over by the PPP bidders. Graham was assigned briefly as the chief engineer for rolling stock for the Jubilee, Northern, and Piccadilly, before being promoted back into LU as control systems engineer and deputy to the then LU head of rolling stock engineering (modesty forbids me…!).
During this period, Mr ATO came to the fore again,
supporting the introduction of ATO in the open areas of the Central line where
there was a particularly challenging requirement to deliver a service braking
rate of 0.7m/s2 in some areas of known poor adhesion.
He also advised Metronet BCV on the replacement of the
Victoria line ATO controllers, as the first replacements (see 1980s above) were
now obsolete and could not be kept going until the new trains due in 2010 were
introduced.
In 2004, Graham became head of rolling stock engineering with, inter alia, the role of accepting that the new trains obtained by the PPP contractors were fit to enter service. He made a significant contribution to the technical architecture of the future deep tube lines trains, the first of which has been ordered for the Piccadilly line.
2010s – Graham is an active participant in the Union of International Public Transport Operators (UITP) and is now the chairman of the UITP’s Metro rolling stock group. He has also been a member of the IMechE board since 2011 and has presented at many IMechE events.
He is a member of the IMechE’s Skills Task Force and
contributed to the early drafting of the Level 5, 6 & 7 (T&RS)
Apprenticeship Standards for railway engineering that are now starting to be
used.
It was Graham’s work with the Skills Task Force and with the National Skills Academy for Rail that highlighted the first of the five gaps that Graham explored in the next part of his address.
Bridging the Skills Gap
Over the last 10 years (at least) most Railway Division chairmen
have highlighted the skills gap in the industry. Graham commented that those of
us who already work in rail engineering know how endlessly fascinating it is
with, usually, new things to learn.
The challenge, therefore, is to get that message across and
attract youngsters into roles that will engage them for life, overcoming the
common portrayal of a staid, old fashioned industry.
Rather than spanners, hammers and oilcans, we need to show students that work with computers, even artificial intelligence, and working in ordinary work clothes, is now more often the norm. His was a call to arms for all of us in the industry to “do our bit” to encourage young people and to seek a more diverse workforce.
Bridging the BREXIT Gap
Graham’s take on BREXIT focussed on economic and people
impacts. But, with events on the political stage moving so fast (or is it so
confusingly?), between drafting and publishing this article the situation might
have changed.
With that health warning, Graham said: “As I see it, the long
drawn out BREXIT process has, and will have, a profound impact on the future of
the UK rail industry. From a purely rolling stock engineering perspective, our
train builders come from Europe or the Far East and those train builders source
the component parts for their trains from either within Europe or from within
the UK – the choice for them is one of cost, performance and logistics.
“The uncertainty surrounding BREXIT and its impact on UK
trade and sourcing from UK suppliers must affect their purchasing decisions.
Will BREXIT cause currency fluctuations or excise taxes that will increase
costs?”
He added that he had yet to speak to anyone who thought
BREXIT would have a positive impact in the short term, that it could be
disastrous for SMEs who rely on trade with Europe and he is already seeing
signs of far fewer EU applicants for UK rail engineering jobs.
Bridging the economic gap
Provocatively, Graham talked about the bad old days “when,
frankly speaking, railway organisations were treated as ‘cash cows’ for some
monopoly suppliers to milk to their hearts content, where prices were agreed
and profits were boosted by contract variations.”
Perhaps this was stretching a point, but many will recognise
the general principle. Graham went on to emphasise that funding is generally in
short supply or, to put it another way, each pound spent had to deliver maximum
value.
He referred to the changes in his own organisation, where
engineering headcount has been reduced by around 12 per cent, and TfL, like
Network Rail, is working with the supply industry to challenge its own
standards and streamline its processes.
As was shown in a recent RAIB report (Overspeed at Sandy
South Junction, Bedfordshire, 19 October 2018), the challenging of standards
needs its own carefully considered process as changes to standards can increase
risk unexpectedly.
Of course, optimising maintenance and renewals, and making informed choices whether to do work in-house or have it done by suppliers, are all part of the mix. Graham wondered aloud whether the efforts to make the industry leaner and fitter are happening fast enough.
Bridging the technology gap
Graham said: “We are at a tipping point in our industry,
where advanced digital railway systems and the technology they use – more common
on high-density metro systems like London Underground – need to be applied to
our main line railways to overcome challenges with passenger capacity,
especially at complex junctions and to deal with the forecast increases in
passenger ridership.”
He went on to explain that, whilst the metro systems cannot
be transferred directly, as individual lines using proprietary closed systems
are unsuitable for mixed traffic lines and non-compliant with Interoperability
Regulations, “the same professional skill sets, knowledge and experience
present in high density metro railways can be shared and, where used
appropriately, can bridge the technology gap to give UK mainline railways a
real advantage in developing solutions that deliver the required outcomes efficiently
and ‘right first time’.”
Bridging the IMechE/railway gap
Graham referred to his predecessor Andy Mellors who, last
year, spoke about Challenging Times (issue 168, October 2018). “Well, I have to
say, times are still challenging,” Graham said, adding: “We have had a very
difficult 18 months or so in the IMechE. That has resulted in significant
change and my theme this year is all about building bridges.” Graham is seeking
to build new, closer and more collaborative working relationships between all areas
of the IMechE – the volunteer groups, the Railway Division and the other
divisions and groups, the Trustee Board, Council and IMechE staff.
Graham said that delivering engineering change is second
nature to him, but, in this role, he will be delivering people and
organisational change, which is a new skill he is developing. He said he is
lucky to be supported by “a very experienced team of Board members, past
chairmen and volunteers, and I shall be calling on their support heavily if we
are to make the changes we need for our Division and Institution to become more
dynamic and inspirational, driving, motivating and inspiring even more
professional engineering engagement within our railway industry”.
Graham said that it is his objective to provide more relevant
events to allow learning and informal discussions over the coming year and to
grow attendance. He hopes that this initiative will encourage the railway
industry to work more collaboratively with the Railway Division in areas such
as attendance and sponsorship.
Graham explained that the Institution offers the opportunity
for people from across the industry to come together, at the events organised
at headquarters and at centres around the UK, on neutral territory and discuss
matters of mutual interest when competitive pressures can at least be put
partially aside – so-called ‘learned society’ events.
With £50 billion committed to renewals Control Period 6,
Crossrail, HS2 and possibly Crossrail 2, together with 7,500 new main line
vehicles and well over 1,000 for metro and light rail, electrification and
Digital Railway, there’s lots to talk about and lessons to be learned.
Graham added that, against the background of all these
technical developments, the pattern of travel is changing. Whilst passenger
numbers and big city populations are predicted to rise, companies are
increasingly allowing their staff to work more flexibly. Although this trend
might be helpful in depressing the loads during the peak of the peaks, the
shoulders of the peak are likely to extend for longer.
“Indeed, on some London Underground lines we already run a
near peak service for most of the day, in between the rush hours,” he said.
The London Mayor’s Transport Strategy also aims to improve
the air quality in London with the Ultra-Low Emission Zone (ULEZ), which
introduces a daily charge for all road vehicles with petrol or diesel engines
that exceed certain exhaust limits operating within the London Congestion
Charge Zone. The ULEZ is to be extended to cover everywhere within the North
and South Circular roads by April 2021.
Whilst this is likely to give a significant improvement in
the air quality within London, it is also likely to increase ridership on the
capital’s public transport systems and put pressure to provide carbon-free
propulsion on the last all-diesel rail terminus at Marylebone.
Conclusion
Rounding off his address, Graham concluded: “I started my
career 48 years ago as a rolling stock apprentice, destined, at that time, to
become a rolling stock maintainer.
“Along the way, I met and worked with some really great
people, many of which saw in me greater potential than I saw in myself. Those
people shared their knowledge, skills and experiences with me and made me a
better engineer by doing so, thereby helping me to deliver professional
engineering activities that have resulted in my being where I am today in the
IMechE, the IET and at TfL Engineering.
“I’ve often said ‘you’re only as good as your network’,
because it is impossible to know everything and this ethos means that you
develop a very wide group of friends, colleagues and experts, that you can
trust mutually to give good, sound advice when it is needed, and thereby help
to make reasoned, informed decisions when they need to be made.”
Graham advised anyone joining the rail industry to listen and learn as much as possible, as early as they can, from those that have the experience, but never forget that learning everything is impossible and to cultivate those career long friendships and seek out the advice of experts when you need to. It is this type of ethos that will make you a professional engineer, a good team player and eventually a good leader.
Thanks to Graham Neil for his help in preparing this article. Note the views in this article are the Presenter’s own and are not necessarily those of TfL.
It is always a pleasure to report on the Institution of
Mechanical Engineers’ Railway Challenge, as Rail Engineer has done since the
first competition in 2012. Experiencing the enthusiasm, energy and ingenuity of
the teams taking part, seeing the professionalism of the senior engineers from
the Institution’s Railway Division who volunteer to run the event and the opportunity
to experience the Stapleford Miniature Railway make this a thoroughly enjoyable
weekend for all concerned.
The Railway Challenge requires teams of graduates, students or apprentices to design and build a 10¼ inch gauge miniature locomotive that must compete in various challenges, with marks also given for reliability. Before the locomotives can enter these challenges, they must pass static and dynamic scrutineering to confirm that they are built to specification and safe to run. Teams are also assessed on their design and innovation reports and how they present the business case for their locomotive.
This year’s challenge took place on 28, 29 and 30 June. It
was run in accordance with its rules and a technical specification which is, as
far as possible, performance-based. The intention is to encourage novel ideas –
in past competitions these have included the use of springs for energy recovery
and hydrogen fuel cells for traction, which was first seen in the UK at the
Railway Challenge.
As always, the challenge took place on the 10¼ inch gauge Stapleford miniature railway, near Melton Mowbray, run by the Friends of the Stapleford Miniature Railway (FSMR). This has an impressive collection of locomotives and is one of the UK’s largest such railways. It is considered to be ideal for the Railway Challenge, especially as it is not normally open to the public.
Ringing the changes
Over the years, it has been interesting to see how the
Challenge has developed, although some things, such as the enthusiasm of the
teams, don’t change. Also, as the table of previous results shows, for the past
few years only around 70 per cent of the locomotives present were able to
undertake the dynamic tests. Ensuring all systems are operational on a recently
built or modified locomotive is a significant challenge and it is not unusual
for a team to spend most of the night repairing their locomotive. As will be
explained, fried electronics were a significant problem this year.
What does change is that each year there are new challenges
and variations to the rules and technical specification. This year saw a new
auto-stop challenge, which required the locomotive to stop exactly 25 metres
after passing a marker provided by the team. A recent rule change concerned
refuelling. Prior to 2018 this rule stated that refuelling shall not comprise
the replacement of energy storage assets (batteries) and should be done in 90
seconds. Since then, this rule has been changed to allow battery replacement
within a refuelling time of 120 seconds.
In 2018, following this rule change, three of the ten competing locomotives were battery-powered. This year, with the same number competing, eight were powered by batteries.
Also new this year was a schools’ event, which Jelena
Gacesa, operations manager of the IMechE’s education programmes, had initiated
by inviting Leicestershire schools to an educational event during the
competition. About a dozen pupils from Inglehurst Junior School in Leicester
took up this invitation.
This involved a competition to build the tallest working
model lighthouse, seeing the teams work on their locomotives, a ride on the
railway and a quiz on what they had seen.
The quiz’s requirement to draw a picture of a railway carriage of the future brought some interesting responses. One of the teachers present, Debbie Walsh, felt that the event fitted well into the design and technology module in the school’s curriculum. Encouraging youngsters to consider an engineering career in this way is a worthwhile initiative and it is hoped that this will be expanded during next year’s Railway Challenge.
Introducing the teams
Of the 14 teams that entered the competition this year, only
10 were able to bring a locomotive to Stapleford. Of those unable to attend,
Helwan University in Egypt, South Western Railway with CEMAST college and the
University of Warwick had submitted design reports with the latter submiting an
innovation paper.
This year saw two teams from the European continent, the
joint team of FH Aachen University and Reuschling GmbH from Germany and Poznan
University of Technology, whose journey from Poland to Stapleford had taken 21
hours. Also present was a large team from several Thai universities, including
Suranaree University, who have started building the locomotive that they intend
to enter in next year’s Challenge.
The UK universities entering were Brunel, Sheffield and
Huddersfield and there were company teams from Network Rail, Ricardo Rail, SNC
Lavalin and Transport for London (TfL). There was also a joint Bombardier /
University of Derby team.
The new entrants this year were Network Rail (supported by
the University of Birmingham) and Poznan. SNC Lavalin, formerly Interfleet, has
entered all eight Challenges to date. Huddersfield and TfL were also veterans
of the competition with respectively seven and six entries.
Brunel’s pneumatic powered entry bore a strong resemblance
to a steam locomotive. Sheffield’s two-unit locomotive was also distinctive,
with its clear cover and semi-circular body section. Ricardo had the look of a
retro diesel locomotive whilst others had striking liveries. For example, TfL’s
entry was painted to resemble the preserved 1923 Metropolitan Railway electric
locomotive ‘Sarah Siddons’.
As previously mentioned, eight locomotives were powered by
batteries which had the capacity to operate the locomotive for three hours
without refuelling. The exceptions were Huddersfield and Brunel, whose machines
were powered by 7kW petrol generator and 8kW petrol powered compressor respectively.
Although the norm was a battery-powered single-unit locomotive on two four-wheeled bogies, there were significant design variations in respect of auto stop arrangements, braking systems, electronic control, suspension and bogie design. Poznan had a particularly elegant bogie design, with the frame manufactured from an aluminium / polyethylene composite and carbon-fibre composite primary leaf springs.
A challenging plan
The Railway Challenge requires the teams to undertake
presentation and track-based challenges. The four presentation challenges with
their maximum scores were: design (150); business case (150); technical poster
(150) and innovation (150). The design and innovation challenges are the only
ones judged beforehand, based on submitted reports. The poster challenge is
judged during the weekend, as is the business case challenge, based on the
team’s presentation to the judges.
The seven track-based challenges were: energy storage (150);
traction (150); ride comfort (150); noise (150); auto-stop (150); reliability
(300) and maintenance (150).
Except for the maintenance challenge, these are all dynamic tests that require the locomotive to have passed scrutineering before it can run on the railway. This requires the collection of a set of seven coloured stickers, awarded when a scrutineer has confirmed the safety calculations, undertaken a physical inspection, seen the user guide, together with the required markings, as well as indications and evidence of reliability.
Once this has been done, dynamic scrutineering examines the
required safety performance, primarily braking and speed control.
Undertaking these tests, allowing for test runs, a rescue locomotive and spectator trains, requires a detailed operational plan that is sufficiently flexible to accommodate inevitable changes during the weekend. Bridget Eickhoff of RSSB, as the IMechE’s operational controller, had the job of managing this plan to ensure the Challenge ran smoothly.
The plan was for most locomotives to be unloaded on the
Thursday night, with the remainder unloaded on the Friday when all the static
and dynamic scrutineering was undertaken, together with some of the maintenance
challenges. On the Saturday the remaining maintenance challenges were completed
and each team gave their business case presentation. They also had the
opportunity to give their locomotive a 45-minute test run.
All the dynamic track-based challenges were run
on the Sunday, when the FSMR also ran steam-hauled trains for the dozens of
spectators who witnessed the challenges from the Haven.
Sunday’s
operational plan required that, during each hour, a spectator train would run,
two locomotives would undertake their dynamic challenges and a rescue
locomotive would be available to assist either locomotive if required. The
planned movement sequence during each hour was as follows:
Spectator train leaves the station and proceeds
around the loop to point G;
Once the spectator train has passed the signal
box, Challenge locomotive No 1 and its train leaves the station followed by the
rescue locomotive. This locomotive does the auto stop challenge. It and the
rescue locomotive move clear of the points at the Haven signal box;
The spectator train departs for the station.
locomotive No 1 does the ride comfort test and stops at point E followed by the
rescue locomotive;
When the spectator train arrives at the station,
locomotive No 2 departs, it undertakes the auto stop challenge and moves clear
of the points at the Haven signal box;
Locomotive No 1 completes the energy storage
challenge, whilst locomotive No 2 does the ride comfort challenge and stops at
point E;
Locomotive No 1 does traction and noise tests
and returns to the station. The rescue locomotive follows it to just before
point H;
Once locomotive No 1 is at the station, the
rescue locomotive stays ahead of locomotive No 2 whilst it completes its energy
storage, traction and noise challenges. The rescue locomotive and locomotive No
2 then return to the station.
In this way, with the railway operating at its capacity, two locomotives an hour were put through their challenges. Thus, assuming an intensive seven-hour operational day, 14 is the maximum number of locomotives that can be put through the dynamic track-based challenges. However, there are plans for alterations to the railway that will significantly increase this number.
Fried electronics
On the Friday, the maintenance challenge saw the start of the contest as teams demonstrated how fast they can remove and replace a powered wheelset. The time each team took to do this varied from 2½ to 27 minutes and was largely a reflection of the way their locomotives were designed to meet this challenge.
To ensure that this challenge was conducted in a safe
manner, it was done in accordance with an approved method statement and
undertaken in several stages. After each stage, the stopwatch was paused until
the judges confirmed that it was safe to continue.
As well as the maintenance challenge and scrutineering,
Friday and Saturday also saw much work done on the locomotives to resolve
various problems. Some of these reflected the lack of testing, as some teams
had only run their locomotives on short tracks by the workshop. Hence, not all
locomotives had been run at full power for long periods or experienced the harsh
vibration environment and impact loads from continuous running.
The most significant problem was fried electronics, with some teams suffering burnt out motor controllers. This was an issue for Poznan and Network Rail, whose locomotives operated at reduced power as a result. Part of the information that the Institution provides to the teams is a useful ‘technical tips’ presentation. This includes a slide showing that traction components need to be significantly over-rated as traction motors have a spikey current profile.
Nevertheless, despite these problems on the Friday and
Saturday, all the teams, except for Brunel, were able to take their locomotives
for a test run around the railway’s 2.6-kilometre long circuit, although the
Poznan locomotive had to be pushed back by the FSMR’s rescue locomotive.
Unfortunately, Brunel was not able to overcome the problems
associated with the unique design of its locomotive.
Thus, it looked as though Sunday would see the previous
maximum of seven locomotives doing the dynamic challenges being exceeded.
However, this was not to be as, Brunel could still not run, SNC Lavalin had a
burnt-out motor controller and, unfortunately, as Poznan’s locomotive left the
station, it was damaged after it hit an obstruction and was unable to proceed
further.
The first hour of the day saw Ricardo and Aachen’s
locomotives running exactly to the operational plan. Thereafter, due to
locomotive availability, only Bombardier/Derby and TfL shared an hourly slot
and Sheffield, Huddersfield and Network Rail ran alone during their challenges.
Some of the locomotives were unable to undertake all the
tests. For example, when starting, Huddersfield’s locomotive suffered from a
jerky traction control which prevented it starting on the gradient for the
traction and noise challenge. With burnt out controllers, the underpowered
Network Rail locomotive could only do the ride comfort challenge and required
the FSMR rescue locomotive to push it up the gradient back to the station.
All this was observed by dozens of spectators from their
vantage point at the Haven, who were kept informed by Rail Engineer’s own Nigel
Wordsworth and his megaphone. The track challenge results were also displayed
on a scoreboard.
The spectators were well placed to see how the locomotives tackled the new auto stop challenge, in which a track-side marker of the team’s own design had to be used to command the locomotive, travelling at a speed of not less than 10km/h, to stop at point B, 25 metres beyond the marker. The wide variety of markers used included lengths of rail between the track, an infra-red control from inside a TV remote, ultrasonic detection, a traffic cone and caravan reflector. Unfortunately, of the six locomotives entering this challenge, only two stopped within five metres of point B and so were the only ones to score points.
And the winners were
There was tension in the air as everyone waited for the
prize-giving. After a short delay, the appearance of chief judge Bill Reeve
signalled that the judges’ deliberations were complete. Bill advised that, in
the view of the judges, this had been the best Railway Challenge yet, with some
real innovation in design, and everywhere there had been real enthusiasm and
commitment from the teams.
Before declaring the overall winner, awards were made for
the individual challenges. In addition to the track challenges shown in the
table, the winners of the presentation challenges were:
Design – jointly won by SNC Lavalin and TfL;
Business Case – TfL;
Poster competition – SNC Lavalin;
Innovation – University of Warwick.
Although not present, Warwick had won its award for an
innovation report entitled “a study of efficiency improvement for an electrical
regenerative braking system.”
The other challenge award was for reliability, which was jointly given to Sheffield and Bombardier/Derby which had each achieved a not-quite-perfect 290 points out of 300.
In addition, this year the judges gave a discretionary award
for something that particularly impressed but was not reflected in the
challenges. This special award was given to Poznan for innovation and elegance
in mechanical design in respect of the composite bogie frame and leaf spring
bogie.
Then it was time to announce the top three teams. In third place was Ricardo with 1099 points, narrowly beaten by TfL’s 1100 points. The overall winner was Aachen with an impressive 1389 points. Team captain Robin Muhlmeyer commented “We are participating now for the third time in the Railway Challenge and have continued to make progress each year. This time it was enough for us to take the trophy back with us. It’s always an incredible pleasure to be here at the Stapleford Miniature Railway.”
It was then time to thank those who had made the challenge
possible, including the Institution’s staff, the sponsors (Angel Trains, Beacon
Rail Leasing, RSSB and the Young Rail Professionals Group), support from
Network Rail and, last but not least, the unstinting support from FSMR personnel
who ran the railway during the challenge. FSMR is also actively supporting
planned enhancements to its railway that will enable the challenge to
accommodate up to thirty locomotives in future.
As the Railway Challenge goes from strength to strength each
year, this expansion plan will no doubt be required as more organisations wish
to enter so that they and their young engineers can benefit from it. As Bill
Reeve noted; “When I come to this event, I see enthusiastic teams learning, in
a short period, a huge amount about the realities of engineering projects. I
also see real innovation in engineering design tested here in a low risk
environment.”
Put another way, the Challenge is an excellent way to train and develop young engineers.
Each year, the UK hosts
numerous railway industry events. Most of these concern domestic issues and few
have complex technical content throughout. In contrast, more than half the 150
or so participants at the biennial Railway Engineering Conference held in
Edinburgh were from outside the UK (33 per cent from Europe, 14 per cent from
Asia, eight per cent from USA, plus individuals from Brazil and Australia).
Hence, most of those present had travelled a long way to present their in-depth
technical papers.
There were a hundred such papers, covering all aspects of railway engineering, although track, structures and civil engineering accounted for more than three quarters of them.
The conference is chaired by
Professor Mike Forde of the University of Edinburgh and organised by ECS
Publications, part of the multi-award-winning Edinburgh Railway Group. The
first Railway Engineering Conference in the series was held at Brunel
University in 1998, thereafter the event was held in London until it moved to
Edinburgh in 2011.
This year’s two-day conference was held on 3-4 July. Each day started with keynote presentations, after which papers were presented in three parallel sessions. Two of the keynote presentations were the only ones without detailed engineering content.
Chris Jackson, editor of
Railway Gazette International, gave his review of specific railway developments
in each continent from which he saw globalisation, increasing urbanisation and
decarbonisation to be common worldwide issues. He felt that the data-driven
‘fourth industrial revolution’ had huge implications for asset monitoring,
maintenance, train control and automation for which the critical challenge is
attracting and developing new skills.
Professor Rod Smith asked
whether railways in rural areas were a financial drain. His key point was that
high fixed infrastructure costs don’t change much with use. Therefore,
proposals for lightweight rail vehicles showed an inability to learn from
history as such vehicles do not satisfy the requirement to make the best use of
the infrastructure. In this respect, the UK has one of the best records in Europe
with 11,200 passenger-km/route-km/day, although this compares poorly with
Japan’s 40,900.
High speed track
Niall Fagan, HS2’s head of
track engineering, explained the thinking behind the design of HS2’s track,
which will carry 18 trains per hour and over 60 million gross tonnes per annum,
and for which there will be a five-hour overnight maintenance window, with
eight hours on Sunday. Phase one consists of 486 linear kilometres of track and
153 S&C units, for which there is a 20-month construction window.
HS2’s survey grid will be a
snake projection, which has been developed to provide a unified coordinate
system for long, linear projects as the Ordnance Survey grid does not take
account of the curvature of the earth. The difference between the two projections
is 50 metres over the 170 kilometres between London and Birmingham and Niall
illustrated the importance of this grid by explaining why millimetres matter at
the highly constrained Euston approaches.
He also explained the issues that had to be considered to determine HS2’s trackform. These included the predicted tamping of ballasted track, which is largely a function of tonnage carried. It also determines the renewals requirement, as ballast life is a function of the number of tamps. If, as seems possible, HS2 is to consist of largely slab track, measures will be required to prevent ground-borne sound and vibration reaching buildings above tunnels.
By the end of 2018, China has built 29,000 km of high-speed lines, of which more than 80 per cent is slab track. Professor Xuecheng Bian, of Zhejiang University in China, described his research into the mechanisms that trigger mud pumping under slab track, for which polyurethane injection is an effective remedial measure.
He also described how the University had used a full-scale ballasted-track test rig to observe the dynamic responses of ballasted track at speeds up to 360km/h. This showed that high-speed wheel loading increases ballast particle rearrangement, due to greater particle rolling and sliding, and that dynamic ballast settlement was 75 per cent more than that caused by stationary cyclic loading.
As HS1’s head of track
engineering, Dr Sin Sin Hsu is responsible for 109 route kilometres and 143
sets of S&C, of which 62 are high-speed swing-nose turnouts. Her
presentation considered how high-speed line maintenance, especially S&C,
must consider higher dynamic forces, for example HS1’s track maintenance
tolerances are essentially the same as Network Rail’s construction tolerances
for 200km/h track.
Dr Hsu described the complex
geometry of high-speed swing nose crossings. On HS1 these are produced by
Vossloh Cogifer and are 1 in 65, 230km/h turnouts with 152 metres from toe to
nose.
She also gave an example of the
problems of maintaining high-speed S&C – a badly vibrating point machine
which had to be changed every three months. After trying various solutions, the
cause was eventually found to be a one-millimetre rail dip, for which the
solution was a 0.5mm rail grind. She stressed that this showed the importance
of obtaining the correct data to understand the root cause of any problem.
Other high-speed rail papers
included an assessment of critical speed by Pedro Alves Costa of the University
of Leeds, which concluded that this was governed by soil properties up to a
depth of eight metres, and a presentation from the Austrian PORR on the Slab
Track Austria (STA) system.
A team from the SNCF also
presented a paper on a holistic approach for high-speed lines maintenance and
renewal.
Subgrade including asphalt
One of the keynote
presentations was given by Professor Carlton Ho of the University of
Massachusetts, Amherst, on substructure track design principles and how these
differ between the USA and China. He noted that, in the USA, where heavy
freight has axle loads of between 33 and 39 tons, standards are based on the
American Railway Engineering Maintenance-of-Way Association’s (AREMA) Manual of
Railway Engineering (MRE). These are based on geometrics and absence of defects
and so allow railroads the flexibility to use the most appropriate design
practice.
In contrast, in China, track
design is more prescriptive as it must meet the various codes for different
aspects of railway engineering.
Professor Ho’s presentation featured probably the longest equation presented to the conference, for the amplitude of elastic displacement of the subgrade bed.
Two presentations considered
transitions at bridges. Giacomo Ognibene of the University of Southampton has
studied ballasted railway bridge transition using a finite element model to
assess the effects of train speed, sub-base soil and under sleeper pads and
found that both the train speed and the sub-base material affect transition
performance. In particular, it was found that a stiffer, wedge-shaped backfill
mitigated the support stiffness variation at the bridge approach.
A paper by Stark and Wynn of
the University of Illinois, Urbana, considered ballast-based reinforcement,
mechanically stabilized earth reinforced walls, and geosynthetic reinforced and
pile-supported embankments (GRPE). This concluded that segmental retaining
walls with geosynthetic reinforced soil is a cost-effective solution to
mitigate differential movement at railway/bridge transitions and that GRPEs are
a more cost-effective method than unreinforced pile-supported embankments for
the reduction of soil deformation.
Professor Jerry Rose of the
University of Kentucky is clearly a fan of asphalt. His presentation described
the benefits from the US railroad industry’s selective use of a 25-37.5mm
hot-mix asphalt layer in the track substructure since the 1980s. It described
how testing such trackbeds, from 12 to 29 years old, had shown that the asphalt
had no brittleness, weathering, or deterioration due to the insulating effects
of the overlying ballast. The benefit of its load bearing properties was
evident from the asphalt mat being subject to typical dynamic pressures of
13-17psi from the heaviest freight trains whilst the layer below it is subject
to 5-7psi.
The use of asphalt outside the USA
was considered by Dr Diego Cardona of Eiffage Infrastructure in France. His
presentation showed that Italy first used it in the 1970s, for the country’s
first high-speed line between Rome and Florence, and now has 1,200 kilometres
of asphalt track. In France, a short trial section of the Paris to Strasbourg
high-speed line was provided with an asphalt mat in 2004.
After this was shown to require
much less tamping than the rest of the line, a further 283 kilometres of French
high-speed lines have been built with an asphalt base. Short lengths of asphalt
track are in use in Spain, Germany and Austria, where the first asphalt
trackbed laid in 1967 had not required any maintenance by 2011, 44 years later.
There is also widespread use of asphalt trackbeds in Japan for high-speed and
conventional lines.
Dr Cardona noted that this experience highlighted the reduction in both maintenance and line closures from the use of asphalt, which had justified its higher initial cost. However, the use of asphalt required careful consideration of drainage requirement, due to its higher run off, and the need for tamping and ballast cleaning to take account of the asphalt layer.
Drainage and Flooding
With 300,000 hours of delay
recorded each year in the UK due to flooding issues, papers considering how
potential drainage problems could be better analysed and predicted were well
received. A joint paper produced by Network Rail, the University of Birmingham
and the University of Lampung in Indonesia proposed a better method to understand
underlying problems and failure mechanisms associated with drainage failures.
This used expert input to produce a fault tree with 22 casual factors basic
events, eight casual factors mid events and three failure modes leading to one
top event.
When this method was used to
investigate drainage failures at Ardsley tunnel, it was concluded that the
underlying problems were change in land use, resulting in increased surface
runoff, changes to drainage upstream and damage caused by others or third-party
assets.
Yiqi Wu of the University of
Sheffield and Raja Jamie of Network Rail presented a Markov chain model for
predicting the degradation of various classes of railway drainage assets. This
approach, a widely used probabilistic model for simulating infrastructure
deterioration, considered the influence of various factors, such as
construction material, size, shape and location, to quantify the rate of the
degradation on all 329,781drainage assets on Network Rail’s Ellipse database.
Cowley Bridge Junction between
Tiverton and Exeter St Davids has been subject to frequent flooding and
washouts as described in issue 169 (November 2018). Here, the depth and
velocities of flows overtopping the railway have exceeded 0.5m and 0.5m/s
respectively. This is due to the complex hydrology and character of the River
Exe system, which has a sinuous channel that meanders severely back and forth
beneath the mainline.
In their presentation, Sinead
Lynch and Thomas Mymors of Arup described the complex hydraulic modelling process
used to determine the best flood mitigation option, which was the selective
lowering of the flood plain on the approach to the embankment into which twin
concrete box-culvert sections, 3.5 metres wide x 2 metres high, were inserted.
Earthworks and Bridges
Although the closure of the
railway at Dawlish highlighted its vulnerability to the sea, the stability of
the 50-metre-high cliff above it poses an equally serious problem. As Tim
Laverye of Network Rail described in his presentation, there have been 50
recorded cliff failures in the vicinity. He described the current mitigation
for such failures, including numerous sensors in the cliff and its drape
netting, and outlined plans to ensure the long-term resilience of the railway.
The many issues to consider include the complex groundwater regime and the
nature of the dominant Teignmouth Breccia strata.
The problem addressed by the
paper produced by Raynor and Bennett of Ove Arup is the design of OLE
structures. In a wide-ranging presentation, this addressed ground
investigations, selection of foundation type, constraints of construction plant
and the need for cost effective design. For example, it showed how pile depth
could be reduced, resulting in only a slight increase in permissible contact
wire movement.
The fatigue life of riveted
railway bridges was the subject of the paper presented by John Mander of Texas
A&M University. He noted that, whilst appropriate for new bridges, current
conservative design codes are not helpful in assessing the remaining life of
older structures. His paper outlined a systematic process that considered both
initial fatigue-life and post-crack fracture propagation life through to
fracture. This gives a 20 per cent life extension beyond crack initiation,
providing a grace period for remedial repairs.
The longevity of masonry
bridges was considered by Manicka Dhanasekar of Queensland University of
Technology in Australia. He described how digital-image correlation had been
used to determine the deformation of masonry arches and a flat jack method was
used to measure the elastic properties of aged masonry. This showed that the
maximum deformation at the crown of a 150-year old bridge was 0.5 mm for
freight trains and that the absolute maximum strain was well within the limit of
the masonry arch barrel.
Safety and Environment
The paper “Are Hydrogen trains
the answer?” was one of the few about rolling stock. This was presented by your
writer and considered the environmental benefits and limitations of hydrogen
trains. It concluded that they are not the answer to “life, the universe and
everything”.
Loss of refrigerant contributes to greenhouse gas emissions and air conditioning failures. In his presentation, Andrea Stanio of Alstom described how a virtual twin of each train’s HVAC system, coupled with sensor data acquired from the associated physical counterpart, can provide accurate assessment of the actual amount of refrigerant in the system. This reduces both the cost of maintenance of the air conditioning system and the risk of its failure.
Comparing different
optimisation algorithms to analyse metro eco-driving was the subject of a paper
presented by the Universitat Politècnica de València. This was intended to take
advantage of the advanced communications between train and track, which now
make it possible to define multiple speed-profiles for ATO (automatic train
operation) systems.
This study compared genetic
algorithms with the particle swarm optimisation algorithm inspired by the
collective behaviour of insect colonies and concluded that, in terms of spread,
the swarm algorithm performed better.
Two papers considered train
derailments. Shinya Fukagai of Tokyo’s Railway Technical Research Institute
considered how the size of machining marks after tyre turning can increase risk
of wheel-climb derailment. Richard Bullet of Arup referred to historic
accidents as he considered mitigation for the risk of bridge collapse after
derailment.
Using an intelligent vision
system to improve platform safety was the subject of a presentation by Howard
Parkinson of Lancaster University. In it, he identified the potential for such
systems to detect potentially dangerous situations, including automatic
indication on the driver’s monitor, and reduce platform dwell time. He also
identified the issues that a pilot scheme would need to address.
Prize winning presentations
The presentations mentioned in this review are about a quarter of those presented at the conference. They are, of necessity, an arbitrary selection of the 98 presented to the conference, but they give an indication of the breadth, the intellectual rigour and complexity of the issues covered. Four of the papers were given special prizes. These were:
Best paper by a university researcher: “Analysis
of a bridge approach: Long-term behaviour from short-term response” by G.
Ognibene, W. Powrie, L. Le Pen, J. Harkness of the University of Southampton;
Best engineering application paper: “A holistic
assessment approach for high-speed lines maintenance and renewal” by A
Dhemaied, G Saussine, S El Janyani, Q A Ta, J M Cornet, J Lossignol, M
Koscielny, A Schwager Guillemenet, A Hily C Renaud of SNCF;
Railway Gazette International innovation award:
“Proposal of track renewal method using prepared concrete method” by S Matsuo,
T Fujioka, S Watanabe, I Arai,Y Yonehara, S Kubota of the Tokyo Metro;
Best Paper demonstrating use of Geophysics and
NDT: “Autonomous vehicle-track interaction monitoring to improve infrastructure
maintenance” by S Jovanovic, P Tešić, University of Novi Sad, Serbia and M Dick,
Ensco Inc, Springfield, USA.
The award for the best
exhibition at the conference was jointly awarded to edilon)(sedra and Staytite.
A lifetime achievement award
for distinguished international service in the field of railway track
engineering was also awarded to Dr Jerry Rose of the University of Kentucky. A
surprise award was that given to Edna Forde for her contribution to the
technical development of the PWI by the Institution’s technical director, Dr
Brian Counter.
With many of those present travelling
half-way around the world to present their papers, the conference demonstrated
that railway engineering is an international community from which there is much
to learn. It would be good to know if some of this international practice is
adopted in the UK as a result of this conference.
The biennial international fair of Russian-gauge railway equipment that is PRO//Motion.EXPO took place over four days at the end of August. This year was the seventh such show, which offers static and dynamic exhibits, extensive exhibition halls and conference presentations, with over 700 companies present. It was held at the Scherbinka test facility, 30 kilometres south of Moscow, which opened in 1932 and has a circular test track, six kilometres in circumference.
The impressive event showcases the latest 1,520mm-gauge
railway equipment and offered visitors both the opportunity to hear conference
presentations which offered international insights and the chance of a close-up
examination of the latest Russian-gauge rolling stock.
A highlight of the show is the ‘Dynamic exposition’, in
which locomotives are run on the circular test track. This year’s show included
nine preserved steam locomotives, Russia’s first mass-produced 3kV DC electric
loco, introduced in 1938, and the latest freight locomotives.
These included the protype two-unit 2ES5S 25kV AC freight
locomotive, unveiled by Transmashholding (TMH) last year, which has an
autopilot and pre-emptive self-diagnostics and recently completed 5,000
kilometres of test running at Scherbinka, hauling 6,900 tonnes at up to
120km/h. As a result of a programme to localise the supply chain, 85 per cent
of its value is Russian made. This includes traction equipment, transformers,
compressors and control systems.
Also in the exposition was the 9,300kW three unit 3TE25K, Russian’s most powerful diesel locomotive, also built by TMH. This was introduced on the Baikal Amur main line last year and can haul freight trains of 7,000 tonnes.
Self-driving swallow
The event also provides an opportunity for news releases. On
30 August, the completion was announced of the re-gauging of the rail network
on Sakhalin island, in Russia’s far east and just north of Japan. Until World
War 2, the island was ruled by Japan, hence its railway was originally built to
Japanese 1,067mm gauge. The programme to re-gauge the island’s 700-kilometre
network to Russian 1,520 mm gauge started in 2003.
News from the Expo itself was that Russia’s first
self-driving train had been tested at Scherbinka on the first day of the show.
This was a specially fitted ES2G unit – a high-density version of the Siemens
Desiro EMU variant, known as the Lastochka (Swallow), which operates the Moscow
Central Circle (MCC) service. This line opened in 2016, as reported in issue
158 (December 2017), and already carries 11 per cent of Russian Railway’s
passengers.
This self-driving unit has machine vision using radar, LiDAR
and both conventional and infra-red cameras. It also has infrared motion
sensors that are installed at the train doors to ensure platform safety, as
opposed to the normal worldwide practice of using platform screen doors to
control platform safety of unmanned metro services, and an ultrasonic
positioning system that enables station stops to be accurate within 50
centimetres.
The autonomous train will require several months of testing
to fine tune its algorithms. The intention is that services such as the MCC,
with a large volume of traffic and small distances between stations, will
eventually be operated by unmanned trains, whose operation will be monitored by
a control centre that can operate the trains in an emergency. It is envisaged
that one control room operator will be able to control ten trains, although
this will require the approval of appropriate legislation.
On board the autonomous Lastochka at Scherbinka were the
Deputy Chairman of the Government of the Russian Federation, Maxim Akimov, and
Russian Railways chairman, Oleg Belozerov, who claimed that this
Russian-developed technology was a year ahead of that being developed by
foreign colleagues.
The MCC’s Lastochkas are maintained at Podmoskovnaya depot, which has a data-service centre in which it uses the Siemens Railagent application suite make full use of the fleet’s connectivity, supporting smart monitoring, data analysis and predicative maintenance. As a result, the fleet has an availability greater than 99 per cent. Some of the trains are also fitted with infrastructure diagnostic and rail fault detection systems, to maintain high infrastructure availability.
Shaping the future
In his speech at the opening of PRO//Motion.EXPO, Oleg Belozerov advised that the driverless train on which he had just ridden signalled a new era and highlighted the importance of artificial intelligence. He advised the conference that Russian Railways intends to become a leader in such advanced technologies and that, in particular, the company is focusing on quantum communications, which offer complete protection from hacking. This is because such communication is based on physical principles rather than cryptographic systems.
His address set the conference theme of how railway
engineering technologies can shape the future. In the opening session, speakers
were asked to choose one of twelve technologies that will have the greatest
impact in the next ten years. In most cases, artificial intelligence was the
answer, although some speakers didn’t wish to answer the question as they
considered that it was wrong to focus on just one technology. Other answers
were high-speed rail, big data and 5G as an enabler.
Various presentations featured the use of digital
technologies for asset management, traffic management and train control. This
included the development of unmanned trains, which are being developed for both
freight traffic as well as metro services such as the MCC. In a presentation on
digital railway traffic control technologies, Professor Efim Rosenburg, first
deputy general of Russian Railway’s Research Institute, outlined a strategy to
introduce moving-block signalling with interval regulation by radio.
He envisaged that this would be introduced from 2027 onwards, after initial concept testing. This would be a development for Russia’s KLUB-U train control system, for which there are currently 18,000 in-cab units in service. It would also build on the experience of coupling virtual freight trains by radio on the east Siberian railway.
In another presentation, it was estimated that reducing headways to three-minutes on the MCC, which carried 129 million passengers last year, through the introduction of a hybrid radio moving-block system would cost 13 billion roubles (£160 million) and would pay for itself in five years.
Green technologies
Technologies to reduce the rail industry’s impact on the
environment were also promoted. Introducing the session on green technologies,
Boris Ivanov, Russian Railways deputy head of technical policy, advised that
the company’s carbon emissions had been reduced by 30 per cent since 1990,
though he accepted that this was still not meeting UIC targets.
His presentation showed that Russian Railways has a target
to reduce CO2 emissions by 30 per cent of its 1990 baseline by 2030 and have
carbon-free train operation by 2050. For particulate emissions, the target is a
reduction of 40 per cent of 2005 levels by 2030 and to eliminate them by 2050.
To reduce emissions further, Russian Railways is looking at
alternative energy sources, such as hydrogen. There is also a large-scale
programme to introduce more efficient diesel and electric locomotives.
One such initiative is a programme to introduce battery-hybrid
shunting locomotives, which are estimated to offer a 27 per cent cost
reduction, equivalent to annual savings of nine million roubles (£100,000) per
locomotive. As Russia has 18,000 such locomotives, which spend up to 85 per
cent of their time idling, this initiative offers significant cost and
environmental savings.
Other speakers referred to initiatives to replace diesel
with cleaner fuels such as LNG (liquified natural gas). However, whilst this
will significantly improve atmospheric pollution, it does little to reduce CO2
emissions.
Initiatives to reduce energy use at stations included the
installation of solar panels and heat exchangers, which pay for themselves
within two years.
Hydrogen-powered trains were also mentioned in other
sessions. Alstom’s chief executive, Henri Poupart-Lafarge, described how Alstom
had introduced the world’s first hydrogen train in passenger service and
explained the benefits of this technology. He suggested that its use on rural
routes might result in electrification equipment on little used lines being
dismantled.
Joerg Liebscher, CEO of Siemens Mobility in Russia, described how his company’s Mireo commuter trains can be battery or hydrogen-powered and would use the next generation fuel cells that offer a 50 per cent increase in power density. He advised that there was a great deal of interest in hydrogen powered trains in Europe and that the German government had a 350-million-euro programme for their development.
Other speakers considered that it should be possible to power
freight trains by hydrogen. Whilst this is not possible in the UK, due to
hydrogen storage space limitations, this may be feasible in Russia, where the
use of four-unit freight locomotives to haul freight trains that are one
kilometre long is not uncommon.
As Russian Railways is primarily a freight railway, there
was a range of innovative wagons on display and mentioned in the conferences.
These included articulated wagons with swop bodies, techniques for
lightweighting and a power pack for refrigerated containers powered by an
axle-end mounted hydraulic pump.
A presentation from Korea explained how folding containers had been developed to address the trade imbalance between Asia and Europe that requires containers to returned empty. In a pilot scheme introduced in July, four such folding containers take up the same space as a normal container.
Austrian technology day
Day two of the Expo highlighted rail technology partnerships between Austria and Russia. This was underscored from day one when PRO//Motion.EXPO was jointly opened by Oleg Belozerov and Andreas Reichhardt, Federal Minister for Transport, Innovation and Technology of the Republic of Austria. In his opening speech, Reichhardt noted the deep friendship between Austria and Russia and suggested both countries had much to offer each other. He considered Russia to be a global leader in artificial intelligence and noted that Austria is the world’s fifth-largest supplier of railway goods and services.
The Austrian technology day was introduced by Andreas Mattha,
CEO of ÖBB (Austrian Railways) who noted that both companies had spent time
understanding each other’s markets and that Austrian companies were actively
involved in upgrading Russian Railways’ infrastructure. He stressed the
importance of environmental protection and felt that ÖBB also had much to offer
in this respect.
He also considered that it was important to extend the
Russian broad-gauge network into Vienna by building the proposed 400-kilometre
1,520mm line from to Kosice in Slovakia as described in issue 162 (April 2018).
At an earlier press conference, Alexander Misharin, first deputy managing
director of Russian Railways, advised that this project was proceeding to plan
and that the feasibility study for this new line would be completed this year.
The Austrian technology day also provided an opportunity to
launch a joint Austrian/Russian rail technology platform to market and
co-ordinate research, innovations and bilateral technology projects. Commenting
on this, Oleg Belozyorov noted the importance of this transition from direct
procurements to the creation and promotion of joint products.
The session also provided the opportunity for 14 Austrian
companies to showcase their products and services. In addition to the
well-known names of Plasser & Theurer and Frauscher, this included Calipri,
Linsinger and Kiepe Electric, which manufactures HVAC equipment for various
train-builders including Bombardier, Stadler Rail, Siemens and Alstom.
Calipri produces hand-held, highly accurate profile measurement
devices for wheels and rail. These use the company’s patented principle of
using three laser lines with roll and pitch correction. Linsinger designs and
manufactures rail milling machines, which operate at a cutting temperature of
320°C. This compares with rail grinding temperatures that can peak at 820°C and
may potentially change the microstructure of the steel rail head.
A presentation from Dr Hee-Seung Na, President of the Korea
Railroad Research Institute, provided another international aspect of interest.
Dr Na was confident that the railway across the demilitarised zone between
North and South Korea would soon re-open, following an agreement at the April
2018 inter-Korean summit. He explained how a new route across the two Koreas
could be used to carry containers by rail from South Korea to Europe.
Another interesting perspective was offered by a presentation on the problem of creating a Russian industrial internet of things from Vladimir Betelin of the Russian Academy of Sciences. He noted that, by 2050, 50 billion devices will be connected to the internet and he was concerned that undeclared capabilities on Intel processors, which included auxiliary cores that monitor inputs and outputs, rendered these devices liable to cyberattack. He felt this was a factor in the development of the Stuxnet virus which had reportedly destroyed Iran’s nuclear centrifuges. For these reasons, he felt it was important for Russia to expand its ability to produce microprocessors.
Static display
As the Russian loading gauge is 34 per cent higher than that
in the UK, this British visitor found it an awe-inspiring experience to walk
around the rolling stock on display on the tracks between the exhibition and
conference halls.
Vehicles that seemed to be built to the full 5.3 metre height of this gauge were the double decked coaches, a self-powered liner-tamper and self-powered snow plough that can clear snow at 40km/h.
A much smaller exhibit was the hybrid TEM5X shunter built by
TMH. This has a 200kW diesel engine, lithium-ion batteries of an unspecified
capacity and a 135kN starting force.
One of the latest freight car designs offered by the United
Wagon Company was its articulated hopper wagon. This has a tare weight of 36.5
tonnes and can carry 113.5 tonnes (or 160 cubic metres) of grain or fertilisers
on three bogies, resulting in a maximum axle load of 25 tonnes. Due to the
short gap between their two hoppers, the use of these wagons enables train
weight to be increased.
TBEMA’s high-speed diagnostic coach normally operates in
Siberia and Kazakhstan. It has various cameras and sensors that measure around
200 infrastructure parameters at 160km/h. This includes track geometry, pattern
recognition, structure gauging, rail profile and OLE geometry. The coach
undertakes ultrasonic rail testing at up to 140km/h. This high-speed testing is
possible as there are separate transmitting and receiving ultrasonic sensors.
The coach also has ground penetrating radar.
For a UK visitor, it was also noteworthy for having the only Union Jack to be seen at Scherbinka. This was on the coach’s standby generator, which was provided by Welland Power from the Lincolnshire market town of Spalding.
It would be interesting to compare the capabilities of TBEMA’s measurement coach with Network Rail’s New Measurement Train. Although TBEMA only has offices in Russia, Ukraine, India and Hong Kong, it does have a joint project in France, after SNCF engineers saw its equipment at the 2015 Expo in Scherbinka.
It may well be that the UK could learn from Russia’s
infrastructure measurement techniques. There may also be lessons from its
development of unmanned metro trains on lines without platform screen doors and
plans for a hybrid radio moving block system.
Although these are technically challenging programmes,
perhaps their most difficult aspect is the integration of infrastructure and
rolling stock systems. In Russia, it seems that such integration is supported
by a strong central guiding mind. In the UK, systems integration requires all
parties to have aligned objectives.
Achieving this may be more difficult than overcoming the
technical problems.
Network Rail has released an interim report into the
fatalities that occurred at Margam, near Port Talbot in South Wales, on 3 July
2019.
It looks into what happened on the day and why and how the
accident occurred. The full report, which will be released in a couple of
months, will explore the underlying causes and will make relevant
recommendations.
On the day in question, thirteen permanent way staff left
Port Talbot depot to work at Margam (20 mins away). They arrived just after
08:00, whereupon the team split into two, with one team of seven working in a
planned line blockage at Margam Moor while the other group of six deployed to
Margam East Junction.
Some time later, three of the six were using a petrol-engine
impact driver to tighten bolts in a crossing. They were all wearing ear
defenders due to the high noise levels. When a bolt seized, they all became
focussed on the task with no-one looking out.
Unnoticed, a GWR train approached the site at approximately
70mph. Two men, Gareth Delbridge, 64, and Michael (Spike) Lewis, 58, were
struck and fatally injured while the third escaped impact with just inches to
spare.
How did it happen?
Work had been planned to take place at the Margam East
Junction site during the afternoon in a line blockage. But the safe work pack
contained a second option, to work with unassisted lookouts that afternoon.
One of the six team members was asked to be the Person in
Charge (PIC). He appointed another team member as the COSS (Controller of Site
Safety).
The COSS was told to use the second system in the safe work
pack and appointed distant and site lookouts.
The team of six on site at Margam East Junction decided to
do extra work that wasn’t in the plan, some of which involved noisy plant to
maintain bolts in a crossing.
A group of three, including the COSS, site lookout and
another, moved about 150 yards away, leaving their colleagues to wait for their
return.
However, the three left at the points started to work on the
crossing bolts. There was no appointed COSS with them, no safe system of work
and no distant lookout in place.
The Person in Charge said he would look out then became involved in the work, focussing on the bolts. None of them saw the train coming.
The train driver initially gave warning to the track workers
using the high and low tone of the train horn but thereafter used the low tone
for two long, continuous blasts as the train approached the work group. The
investigation team note the requirement in the Rule Book for the high tone to
be used to give an urgent warning to anyone on or dangerously near to the line.
The Rule Book specifies: “Give a series of short, urgent danger warnings to
anyone…who does not…appear to move clear out of the way of the train.”
It is uncertain whether a series of short high tone warnings,
rather than continuous sounding of the low tone, could have resulted in the
track workers becoming aware of the train earlier.
Various other anomalies are included in the report. These include:
The Safe Work Pack did not specify all of the
work and how it was to be safely undertaken;
The COSS was only appointed that morning;
The COSS had his authority undermined – the PIC
didn’t believe a distant lookout was needed;
The work was started in the morning, not the
afternoon as planned;
There was no safe system of work in place;
The COSS was not with the group involved when
the accident occurred;
The group all became focussed on the task and
were unaware of an approaching train;
The wide experience of the closely-knit group
and familiarity with each other potentially affected their perception of risk.
There are still facts to be determined, and questions to be
answered, which will hopefully be included in the full report when it is
published. In addition, the Rail
Accident Investigation Branch (RAIB) is conducting its own report into the
accident, though these typically take around 10 months to be issued.
The Office of Rail and Road (ORR) has also stated that it is undertaking an investigation.
Reaction
On the release of the interim report, Martin Frobisher,
Network Rail’s safety director, said: “The whole railway family shares the loss
of Gareth and Spike. Nothing will lessen the pain but understanding what went
wrong and learning from that will, I hope, go some way to reassure all those
affected that we will do all we can to stop it ever happening again.
“Today is the first step in that journey as we share an
initial investigation into what happened. We will continue for several months
to look deeper into the root causes before we make recommendations for our
organisation and all of our people for the future.”
Headspans were necessary but now improved resilience is
needed
Generally, the railway electrification schemes that first
emerged in Britain, before the introduction of more recent AC designs, relied
on fairly heavy equipment. Multitrack supports were generally of the portal
type – that is, a heavy ‘goalpost’-style arrangement.
As new designs emerged for the development of the 25kV AC
system in the 1950s, once again multitrack overhead line equipment (OLE)
situations were met by solid structural arrangements. A common example on the
West Coast main line south of Weaver junction was the BICC ‘Welded Road’
portal. Other portals were of
double-channel, structural steel beams.
When British Rail (BR) looked to complete the electrification of the West Coast main line northward from Crewe to Glasgow, the cost of electrification was being seriously challenged by the government. To gain approval for those northbound extensions, BR undertook an extensive review of its existing designs with the intention of reducing both capital costs and the ongoing maintenance that painted portals needed.
What emerged from that review was a new, lightweight,
modularised, headspan-based support system. This new design was used on the
northern extension of the West Coast main line electrification, opening the
route up to electric traction.
Despite its advantages in terms of cost, the headspan does
have issues with resilience and reliability. In particular, the lack of
mechanical independence between registrations means that, in the event of a
problem such as a de-wirement, the impact is significant, affecting multiple
tracks and increasing the time to reinstate the equipment.
To help resolve these issues, engineering consultant Arup
has successfully completed a ‘Headspan to Portal’ conversion project on the
East Coast main line south of Peterborough. Working closely with Network Rail,
Arup has provided a portal conversion design that could largely be installed
during ‘rules of the route’ access.
Arup’s head of electrification, Jonathan Ridley, invited
Rail Engineer to meet him in York and explain the details.
Headspans
Already described as a ‘goalpost’, a portal consists of two
vertical masts which support a single horizontal beam that spans the railway.
The OLE is supported from this beam, one assembly for each line.
An alternative to the portal is the headspan arrangement.
This structure still comprises two vertical masts, but, instead of the beam,
two horizontal tensioned wires (the upper and lower cross-span wires) are
strung between them to locate the OLE. A
third, top wire is a profiled headspan wire, and this provides support to the
overall arrangement.
The headspan does have the advantage of being generally
cheaper and easier to install than the equivalent portal. However, the headspan
is a load-balanced system where the tensions in the wire runs themselves
contribute to the geometric stability.
If one wire run breaks, the design geometry will be lost, since all
other wires will be out of balance. This
type of structure is therefore not mechanically independent and a failure on
one track can well mean all four tracks are out of service.
Headspans require regular maintenance to check the span wire
tensions, and adjustment of the equipment tends to lead to the design and
replacement of assemblies. On high-speed
lines, a mechanical wave, created by the passage of a train pantograph, also
affects the adjacent wire runs.
In addition, headspans can require larger foundations than a
portal, so as to resist a heavy overturning moment caused by the transverse
wire tension.
Headspan wire corrosion issues have also been experienced,
as well as some other disadvantages. For instance, a mid-point anchor (MPA),
where the OLE wires are fixed in position at their midpoint to keep the contact
wire stable, cannot be a single point restraint due to the flexible nature of
the system. This results in a distributed MPA, where the catenary is restrained
over several structures to distribute the load.
Because of these reliability issues, it is now apparent that
headspans are best suited to lower-speed applications or circumstances where
low capital cost would be more important than high availability or
performance. In the UK, headspans have
been installed in large numbers, but their less-than-reliable performance means
they are no longer installed for new designs on main lines.
Improving resilience
With the continued drive to improve resilience within the railway system, and in view of some of the shortcomings and restrictions of the headspan solution, there has been a growing move to seek alternatives or replacements for the wire-based cross-track structure described here. For some time, where infrastructure projects included major reconstruction, headspans have been replaced with new portal structures.
An early example was the construction of Luton Airport Parkway
station, within the original Bedford to St. Pancras electrification project,
where several portals of a new design were installed. Modern designs of portal
boom have replaced the welded rod format of the early years.
Recent experience of a significant number of catastrophic
mainline failures has led to the consideration of the wholesale replacement of
headspans, in order to improve performance and reduce disruption.
During works connected with enabling Crossrail connections
to the Great Western main line on the approaches to London Paddington, there
arose a need to make numerous alterations to the overhead line configuration
due to staged track layout changes.
Arup became involved in the proposals, as designer for the
scheme. The ‘Old Oak Common and Paddington Approaches’ (OOCPA) phase of the
works involved complex staging, with continuous rearrangement of track layout
and the accompanying stage-by-stage rearrangement of the OLE. However, the
existing electrification scheme utilised headspan structures, as that was the
standard design protocol at the time of construction in the early 1990s.
Analysis carried out by Arup confirmed that multiple sequential rearrangement of OLE on a headspan was not practical, as the balanced-cable arrangement would not allow for the easy rearrangement of individual wire runs, whereas small part steelwork (SPS) on a fixed portal beam could be adjusted relatively easily as the track alignment changed during construction staging.
Designers considered installing new portal structures, but
they also examined the feasibility of utilising the existing steel support
structures and landing a new portal beam on them.
Learning from a Network Rail trial project, at Potters Bar
on the East Coast main line, Arup produced proposals for a practical method of
converting the OOCPA headspans to portals, which was progressed over a small
number of strategic OLE structures. As the headspans in the site formed a
mid-point anchor, a new mid-point portal was installed for practical reasons,
but the conversion of adjacent headspans went ahead as per the Form A design.
Valuable experience was gained from these OOCPA conversion
works. For example, one of the masts on a headspan was found to be rotated by
around nine degrees – not a problem when supporting flexible span wires but
quite inconvenient when supporting a stiff fixed portal beam. In addition, the
installation of the portal beam impacts the type of loading on the supporting
steel.
Portals for Connington
The Connington area, on the East Coast main line south of
Peterborough, experiences relatively high windspeeds and, as such, is prone to
dewirements, resulting in significant train delays over recent years. Network
Rail identified this area for conversion to portals to help build resilience into
the OLE system. Arup was commissioned to prepare a design study to look at
replacing several headspans in the area. Again, the provision of installing new
structures was rejected and a detailed analysis of the possibility of reusing
the existing support masts was undertaken.
Using Arup’s well-developed tools for assessing geotechnical
issues and ground conditions, a close study of the foundations was made, to
discover whether they would cope with the varied stresses and loads from the
new portal geometries.
Economy would best be achieved by the reuse of the existing
masts, but these would have been installed in a manner that facilitated the
cross-track wires. Using point cloud
surveys, the precise positions of the masts had to be recorded, along with any
skew or twist as had been seen at Paddington, which would have an impact on the
loading of the finished portal.
Ground engineering studies of the foundations were essential as the original foundations would have been installed to take cross-track stress rather than the new loadings imposed by the beams. This involved a detailed structural analysis to determine the existing foundation loads and compare them with proposed portal loads. Arup’s proprietary software was used both to model the new loads imposed on the foundations and to check the stresses in the Series 1 boom and connection angle to the masts due to the loads of the UK1 OLE, a design first used on the West Coast main line for higher train speeds, and the OLEMI (OLE Master Index) equipment which continued to support the OLE in the conversion.
In summary, the emphasis was on the strength of the
concrete, reinforcing bar cover and the general suitability of the foundation
for the portal conversion. However, without the cross wires, the bending stress
on the vertical structures is reduced.
In all cases, the foundations at Connington were side-bearing concrete –
no piles were involved.
Following these initial design considerations, a detailed
design for thirty structures was prepared, covering this high-risk area on the
East Coast main line. Performance aspirations would suggest that all headspans
in a tension length should be changed, but the complexity of replacing items
such as mid-point anchors and neutral-section supports drove the decision to convert
only the simpler, multitrack headspans within the tension length. Mid-point
anchors, booster transformer structures, and switching structures were among
some of the structures deemed too complex for this phase of the
headspan-to-portal conversion projects.
Installing the Portal booms
Many design and construction meetings were held with the
Network Rail’s works delivery team, accompanied by drawing revisions, such as
extra dimensions, to suit the construction team’s needs on site. Installation
was carried out on site by Works Delivery, acting as principal contractor.
Design acceptance was similarly eased by working with the E&P
(electrification and plant) and structures route asset managers, and the crane
provider was brought in at an early stage.
Staging of the work was very important, particularly on such
a heavily used route. The design, therefore, detailed all of the stages of the
conversion process, not just the finished result, taking into account the
analysis of both mast and boom orientation, the detailed construction
methodology and a view of simple versus complex structure types.
First, after the headspan wire was removed, the new boom was
landed on the two main steel masts, with the two cross wires retained. After
this interim stage, the SPS was modified, in a staged process, to fit in with
site availability and line possessions.
Lifting in the new boom was a complex procedure, each one weighed in excess of a tonne and had to be manipulated into the final position with existing wires in situ, but, once it was in place, the processes became more self-contained. An initial stage-by-stage approach could have led to one road being upgraded at a time, but Jonathan Ridley pointed out that, in practice, all four roads were completed at once.
If an incident occurs, damage is now usually limited to the
single track involved and the equipment can be returned to normal operating
condition in less time than if the failure occurred on a headspan structure.
With the conversion of 30 headspans completed, Arup can look
to the future. The next step is to convert a complete tension length, including
all of the complex structures that were left out in this conversion project.
Further evaluation of the complex structures will be required as part of a new
feasibility study and the performance improvement gain is expected to be
considerable.
Whilst the reasons for the original switch to headspans can
be readily understood, when their low capital cost contributed to obtaining
authorisation for important electrification schemes, it resulted in reliability
that was less than that of the original portals. Now the design has gone back
full circle, to the cost-effective conversion of those headspans back to
portals, delivering the reliability that today’s busy railway needs.
Thickley Wood footbridge at Shildon, County Durham, is unusual but reflects the growth and decline of the local coalfields. Spanning the historic Stockton & Darlington Railway, this bridge dates from 1857, at which time it was a cast iron span of 16.5 metres over the Darlington to Bishop Auckland line.
As the collieries expanded to meet the demands of Victorian
Britain’s industries, so were additional sidings required. In 1868, a second
wrought iron girder span of 10.9 metres was added to the south and, in 1875,
four additional wrought iron lattice spans, one of 7.7 metres and three of 15.2
metres, were added to the south. At this time there were two running lines and
six sidings passing below the bridge.
Although, there had been 27 miles of sidings around Shildon at their peak, by 2018, there were just two running lines and a single siding passing beneath the bridge, with the first three spans being redundant.
The bridge carries a footpath, much used by walkers and
recreational visitors to Thickley Wood. The bridge is just 40 metres to the
east of ‘Locomotion’, part of the National Railway Museum.
The oldest section, ‘span 7’, is cast iron and is listed
Grade II because it is “a single casting of exceptional length”. This includes
a maker’s plate, ‘HARRIS MDCCCLVII MAKER’. John Harris was the Stockton &
Darlington Railway’s resident engineer from 1836 to 1844. He then became
self-employed, and one of his many businesses was Hopetown foundry, in
Darlington, where he cast this bridge.
It was recognised by Network Rail that parts of the bridge were in very poor condition and that substantial investment would be required to return it to full strength.
Local concerns
The 1825 Stockton & Darlington Railway was the
birthplace of Britain’s railway system and was designated in 2018 by Historic
England as a Heritage Action Zone. This is part of a five-year project to
unlock potential investment into the structures and environment surrounding the
Stockton & Darlington Railway with the aim of creating an iconic tourist
attraction that will increase economic growth in the surrounding area. As a
result, any works around it have the potential to be controversial.
In 2018 Network Rail submitted an application for local
authority planning consent for the works as they would affect a listed
structure. This described the removal of the redundant spans replacing these
with an embankment and the refurbishment of the remaining spans. This being the
only realistic economic solution.
These proposals met with much criticism locally. There were concerns that the work would destroy the character of the bridge and the wish was expressed that the bridge should be preserved especially leading up to the bicentenary of the S&DR.
Jonny Ham, Network Rail’s project manager, explained: “The
design stage was a real challenge and we treated the whole bridge as a listed structure,
even though it was only the original three spans that were protected.
“We were conscious that we wanted to be sympathetic to the
design of the bridge, so we replicated the original metal latticework in the
railings of the new ramped access, and painted the bridge in its original shade
of grey”.
In its submission, Network Rail commented: “By maintaining different styles of bridge across the spans, the appearance of the bridge will alter, but this will tell a story of the development of the railway across a period of time. The appearance of the bridge will reflect one altered over the years to accommodate an ever-changing railway and local landscape.”
In March 2018, both Shildon Town Council and Durham County
Council considered the application and raised no objections to Network Rail’s
proposals.
Design
Leeds-based Construction Marine Ltd (CML) was awarded the
£1.6 million contract for the works under its RCDP (Renewals Collaborative
Delivery Programme) framework contract. The project at this point was at GRIP 3
(option selection) stage. CML’s Nigel Lea and Mark Anderson explained to Rail
Engineer how the project was delivered.
CML prepared an options report, based on Network Rail’s remit, with several alternatives being considered for each of the bridge’s seven spans. Network Rail had liaised over a couple of years with Durham County Council to understand which options were likely to be acceptable at this sensitive location, and this guided the optioneering process.
CML prepared an options report, based on Network Rail’s remit, with several alternatives being considered for each of the bridge’s seven spans. Network Rail had liaised over a couple of years with Durham County Council to understand which options were likely to be acceptable at this sensitive location, and this guided the optioneering process.
There was prolonged and more detailed consideration on
costing and practicality of the various options than is usual, to ensure that
the planning application would be very detailed, and the logic fully justified.
The agreed solutions were:
The four redundant 1875 lattice side-spans (1-4) would be removed and spans 1 to 3 replaced with an embankment. This was designed to be a reinforced earth structure, reducing fill requirements but also enabling its footprint to remain much the same as the original bridge, and fit within the adjacent boundary fencing of the ‘Locomotion’ museum;
Span 4 would be replaced with a standard LM footbridge welded steel span. The original pier between spans 3 and 4 was to become an abutment, with new wing walls built from masonry recovered from the demolished piers. The reinforced embankment behind the abutment would be self-supporting but a compressible layer between fill and masonry would be provided to ensure that no thrust would be imposed on the slender pier;
Span 5 (1868 span) would be retained and the wrought iron structure repaired and repainted, timber decking refurbished and full height parapet handrails installed;
Span 6 would receive minor masonry repairs and have a lightweight in-situ concrete deck installed;
Span 7 (the listed 1857 cast iron span), would have stitch repairs to its cast iron cross girders, making good poor historic repairs, and would be repainted. This, too, would have a lightweight concrete deck over the waterproofed jack arches, and improved parapets;
In addition, a second embankment would be formed to provide a wheelchair-friendly access ramp up to span 7 from the former track bed, connecting with the foot and cycleway that connects the town to the museum. This was to be funded by Durham County Council and was designed to be easily removable as it occupies a former track bed that might at some point in the future be required should freight expansion take place.
Construction
Before works began at the end of August 2018, the CML
project team met with representatives of Network Rail, National Railway Museum,
landowners and Friends of the Stockton & Darlington Railway, to fully
explain the scope and timeline of the project.
Following initial site clearance operations, the team
installed a temporary 120-metre access road from the site compound, which was
established adjacent to the ‘Locomotion’ access road. This was designed to cope
with the bulk earthworks deliveries and bridge delivery. Good, regular liaison
with the museum team ensured deliveries of plant and materials did not affect
their peak visitor periods. Crane pads and a large laydown area were
constructed to store the removed and new spans.
The siding into ‘Locomotion’ through span 4, was blocked
throughout the project.
On 15/16 September, the four lattice spans were lifted out
by a 150-tonne LTM 1150 Crane. The 10-tonne spans 1 and 2 were lifted out
during the day and these placed in the laydown area. The crane then de-rigged
and moved forward to lift out spans 3 and 4 during a 23:00-06:00 possession of
the Darlington – Bishop Auckland line.
During November to January, the new reinforced earth
embankment was designed and constructed by Maccaferri using its Terramesh
system. This combined the use of galvanised steel cages to face the embankment
with geo-fabric tensile straps installed in layers as the embankment was
constructed.
The fill for the embankment facing was locally sourced gabion stone, tipped adjacent to the work areas and loaded into the 3000mm wide facing baskets, to create a drystone wall appearance. The central fill was placed by 25-tonne and 13-tonne excavators, a D6 bulldozer and dumptrucks and compacted in 150mm layers by rollers and plates.
The geotextile straps were installed in sequence with the
erection of the facing baskets. Paragrid 80/05 reinforcement was laid every
other layer at the face edge. As the works proceeded, temporary scaffold edge
protection was attached to the baskets.
Pockets of pre-seeded soil mixture were incorporated into
the upper section of the face, which will result in grass-covered walls. The
lower will remain stone-faced, matching the adjacent walls of ‘Locomotion’. The
new access ramp at the north end was constructed using a mix of reinforced
earth and, at the lower ends, natural fill. The steel footway fencing of the
south embankment incorporates a lattice design, reflecting the original
girders, the north ramp has steel, five-rail estate fencing.
The masonry wing walls and repairs to other part of the
structure were carried out by a team from Darlington-based D France Masonry.
They constructed the walls using recovered stone from the demolished piers,
matching exactly the historic masonry.
The new span 4 was fabricated by Britcon Engineering
Services at Scunthorpe and the pre-cast retention units by Ebor Concrete. These
were installed in possession by a Liebherr 160-tonne crane – the bridge unit
weighed 9 tonnes and this planned lift was delayed by two weeks due to high
winds.
The repairs to span 5 were carried out by HS Carlsteel
Engineering. This span has a timber deck, which was refurbished using timbers
recovered from the demolished spans 1-4.
Spans 5 and 7 were wet blasted to Sa2.5, and an M24 paint
system applied by Bagnalls, in a series of Saturday and weeknight rules of the
route possessions of the Darlington – Bishop Auckland line.
Following the blasting, further cracking was identified in
the bottom flange of the cast main beams. A supplementary planning consent for
additional repairs to the listed structure was quickly agreed. These fractures,
together with the known problems with the cross girders, were repaired using
the Metalock stitch system.
The heritage of the site and structure were very much in the CML teams mind during the project. In addition to the use of recovered timber and masonry, the redundant lattice span 4 was donated to the Friends of the Stockton & Darlington Railway. Ross Chisholm explained that this is in store at the Weardale Railway but that they hope to use this as a training project for the next generation of tradespeople. Once restored it will be displayed within the Heritage Action Zone.
The opening of the completed bridge took place on 28 March, attended by 30 representatives from stakeholding groups. Despite their initial concerns at the scope of the works, the Friends of the Stockton & Darlington Railway complimented Network Rail and CML, describing the bridge as a “good job well done” and were very pleased to have been involved in the project.