Trough-Tec Systems (TTS) and Furukawa Electric have announced that following months of open discussion and substantial testing they have satisfied Network Rail that their Recycled-Polymer Cable Management products meets its revised, more stringent fire safety requirements.
When Green Trough cable management systems was first introduced in 2012 to the UK rail network it was rightly subjected to a wide range of entry-level tests. Manufactured from 100% recycled household plastic waste it was and remains the only recycled-polymer cable trough of this material type on the market.
From the beginning, TTS and its partner Furukawa (the manufacturer of Green Trough) took an “open book” approach to product testing. Being completely transparent with clients and testing bodies TTS ensured that Green Trough testing and thus certification was second to none. The composition of Green Trough is one that has always included flame retardant additives mixed in with the recycled plastic which simultaneously provides the optimum balance of mechanical strength and self-extinguishing properties which avoids any compromise on safety or performance.
Updated product acceptance certificates received in October 2024 clearly separate TTS from other non-cementitious cable management products that have been involved in recent fire incidents that have caused severe delay, disturbance and significant cost to the travelling public and infrastructure stakeholders.
Gary Elliott, TTS’s managing director, expressed his sincere thanks saying: “it’s been particularly refreshing to work so openly with the responsible parties at Network Rail, considering how stringent the tests are, and the absolute magnitude of the matter. I for one completely trust the process, and the rigour behind it. I would like to publicly thank them for giving us the opportunity to demonstrate how safe and robust the Green Trough range of products is and would like to reassure existing and future customers of this fact.”
TTS is delighted with this news; its updated Product Acceptance certificates cover both the cable-trough and the combined anti-slip walkway and cable management systems. Green Trough is manufactured from 100% recycled household waste, is halogen free and UV resistant, and as proved by this news 100% safe for use across the network.
TTS, part of the HIRD Group of companies, puts safety, sustainability, and reliability at the heart of everything it does. TTS is the UK and Republic of Ireland distributor of the Green Trough range of cable management systems and combined anti-slip walkway plus an ever-growing range of accessories to the rail, utilities and power generation industries.
Contact the team at TTS for more information on how we can help your project needs:
On Friday, January 31, the Institution of Rail Signal Engineers (IRSE), the Tech Soc and the Institution of Mechanical Engineers (IMechE) are organising a full day seminar and evening networking event titled “Signalling the Future: Engineering and operational insights into ETCS and CBTC”.
This is aimed at operators, suppliers, infrastructure owners and anyone with an interest in railway signal engineering, and will cover:
What are railway clients’ key needs and requirements?
How can CBTC and ETCS deliver these?
How have these two technologies converged and what unique advantages does each hold?
How do the current standards help or hinder?
Interoperability/interchangeability – is it possible?
The planned speaker list (expected running order) is:
• Keynote – Andy Lord Commissioner, Transport for London (TfL), UK • James Dzimba Chief Control, Command & Signalling Engineer, Network Rail, UK • Gary Joynes Principal Engineering Leader responsible for Signalling Strategy, Transport for London (TfL), UK • Jonathan Speak Head of Engineering Delivery, Hitachi Rail, UK • Gerard Scheffrahn European Railway Traffic Management System (ERTMS) Programme Director, Prorail, Netherlands • Steve Allday Independent Advisor to the National Transport Commission (NTC) of Australia • Ankit Dabrai Head of Business Development, Stadler Rail, Switzerland • Keynote – Clive Burrows Group Engineering Director, First Group Plc, UK • Navneet Kaushik Director Systems & Operations, National Capital Region Transport Corporation (NCTRC), Delhi, India • Hugh Rochford Modernisation Strategy Manager for Paris area, French infrastructure Manager SNCF Réseau, France • Daniel Woodland Professional Head of Signalling (North America), TÜV Rheinland • Dave Sherrin Senior Railway Reliability Manager, Elizabeth Line • Govia Thames Link and Siemens – Speakers to be announced • Bavo Lens Infrabel, Belgium
Jane Power, president of the IRSE, said: “CBTC and ETCS are not ‘new’ anymore – there is a wealth of knowledge and experience out there. I’m really looking forward to talking to experts from all over the world.”
The event is being sponsored by Hitachi, Railway Safety and Standards Board (RSSB) and CPC Project Services.
Trough-Tec Systems (TTS) and Furukawa Electric have announced that following months of open discussion and substantial testing they have satisfied Network Rail that their Recycled-Polymer Cable Management products meets its revised, more stringent fire safety requirements.
When Green Trough cable management systems was first introduced in 2012 to the UK rail network it was rightly subjected to a wide range of entry-level tests. Manufactured from 100% recycled household plastic waste it was and remains the only recycled-polymer cable trough of this material type on the market.
From the beginning, TTS and its partner Furukawa (the manufacturer of Green Trough) took an “open book” approach to product testing. Being completely transparent with clients and testing bodies TTS ensured that Green Trough testing and thus certification was second to none. The composition of Green Trough is one that has always included flame retardant additives mixed in with the recycled plastic which simultaneously provides the optimum balance of mechanical strength and self-extinguishing properties which avoids any compromise on safety or performance.
Updated product acceptance certificates received in October 2024 clearly separate TTS from other non-cementitious cable management products that have been involved in recent fire incidents that have caused severe delay, disturbance and significant cost to the travelling public and infrastructure stakeholders.
Gary Elliott, TTS’s managing director, expressed his sincere thanks saying: “it’s been particularly refreshing to work so openly with the responsible parties at Network Rail, considering how stringent the tests are, and the absolute magnitude of the matter. I for one completely trust the process, and the rigour behind it. I would like to publicly thank them for giving us the opportunity to demonstrate how safe and robust the Green Trough range of products is and would like to reassure existing and future customers of this fact.”
TTS is delighted with this news; its updated Product Acceptance certificates cover both the cable-trough and the combined anti-slip walkway and cable management systems. Green Trough is manufactured from 100% recycled household waste, is halogen free and UV resistant, and as proved by this news 100% safe for use across the network.
TTS, part of the HIRD Group of companies, puts safety, sustainability, and reliability at the heart of everything it does. TTS is the UK and Republic of Ireland distributor of the Green Trough range of cable management systems and combined anti-slip walkway plus an ever-growing range of accessories to the rail, utilities and power generation industries.
Contact the team at TTS for more information on how we can help your project needs:
Siemens Mobility has been awarded four significant contracts by HS2 Ltd and will join key contractors under the Rail Systems Alliance. Siemens Mobility will play a crucial role in the delivery and operation of the new 225-kilometre-long British high-speed railway that will connect London and the West Midlands.
The contracts Siemens Mobility has secured are:
Command, Control, Signalling & Traffic Management (CCS&TM) – Siemens Mobility will implement trackside Automatic Train Operation (ATO) over European Train Control System (ETCS) Level 2. This is the first time for a high-speed rail network, enabling semi-automatic train operations (Grade of Automation 2) for improved capacity, punctuality and energy efficiency. Siemens Mobility will provide technical support services for the system for at least 15 years.
Engineering Management System – delivery and maintenance of a system that will enable real-time control and monitoring of railway equipment, ultimately enhancing reliability and efficiency, using Siemens Mobility’s Supervisory Control and Data Acquisition (SCADA) technology. Siemens Mobility will provide technical support services for the system for at least 15 years.
High voltage (HV) power supply systems – in a joint venture with Costain Ltd, Siemens Mobility will design, install, and maintain high voltage power supply systems along the HS2 route. Siemens Mobility and Costain will provide maintenance services for the system for at least seven years.
Operational Telecommunications and Security Systems – designing and implementing Operational Telecommunications and Security Systems for the entire HS2 route and maintaining the systems once in operation. The company will provide technical support services for the system for at least eight years.
All awarded contracts are expected to start in 2025 with a total order value of approximately £560 million, including long-term maintenance agreements, and potentially including additional options.
These orders are in addition to Siemens Mobility’s £47 million integrated station information management system framework contract with HS2, awarded in 2024.
Rob Morris, Joint CEO, Siemens Mobility UKI said: “HS2 is going to transform rail travel in Britain, and we’re delighted to be playing a key part in delivering it.”
“Our work for HS2 will help in sustaining British jobs and skills from our UK based workforce, and in our 2,500 strong supply chain.”
“We’re already committed to investing £100 million in a brand-new digital engineering, manufacturing and research and development centre in Chippenham which will now play a key role in delivering HS2.”
Construction of a 14,500-tonne box structure designed to take the new HS2 line under the A46 Kenilworth Bypass in Warwickshire has taken a major step forward, following the successful installation of 120 gigantic beams.
The concrete beams, ranging between 13 metres and 24 metres in length were carefully lifted into place using three giant cranes to form an integral part of the structure’s top. A dedicated team of engineers worked round the clock to successfully complete the entire operation ahead of schedule in just 14 days.
Due for completion later this year, the huge box is currently being built on land next to a section of the A46 rather than constructing it beneath the carriageway itself – avoiding the need for up to two years of traffic management measures.
With the beams now in place on top of the box, the finishing touches include completing the deck – the flat surface placed on top of the beams – and installing parapets. In spring, the completed structure will be moved into position under the existing carriageway using an innovative technique.
This will involve a jacking mechanism, designed by specialist civil and structural engineering company Freyssinet, which will push the box across on a guiding raft at a speed of up to 2.5 metres per hour for a total distance of 64 metres.
Together with National Highways and its construction partner for the West Midlands, Balfour Beatty VINCI (BBV), HS2 has started preparing for the box push procedure.
A section of the A46 between Festival Island (Coventry) and Thickthorn Island (Kenilworth) will be closed for two weekends next month for the first stage of preparation work – with plans to move the structure into position during a full closure of the A46 Kenilworth Bypass in spring 2025 for up to three weeks.
default
During the two weekend closures, from 8pm on 7 February to 6am on 10 February and from 8pm on 14 February to 6am on 17 February, HS2 engineers will upgrade road safety barriers, adjust the layout of the central reservation and complete advance drainage works under the carriageway.
Vicki Lee, senior project manager for HS2 Ltd, said: “I’d like to congratulate the entire site team for successfully moving such a large number of beams into place and as we approach the final phase of the A46 box’s construction.
“I also thank motorists in advance for their patience as we prepare for the box push in spring and start our initial stage of preparation work during two February weekend closures of the road. This will allow us to carry out important work directly on the carriageway that would be unsafe for our workforce to do during live traffic.”
At peak, a workforce of 130 people will be based on this structure, delivered by HS2’s construction partner BBV.
In recent weeks, construction progress in the West Midlands has seen HS2 complete the first stage of work for the construction of a bridge that will take the high-speed railway line over the M42 motorway. Two 159-metre-long steel spans of HS2’s River Cole Viaducts have also been completed near Coleshill in North Warwickshire, signalling further progress at the project’s Delta Junction.
Between 1994, when the railway was privatised, and the pre-Covid year of 2019, railway passenger numbers more than doubled. Yet over the same period the railway’s cost to the taxpayer increased by 270%. With high fixed infrastructure costs, increasing passenger numbers should have decreased its cost to the taxpayer.
Thus, as shown on the graph, while rail privatisation may have been successful in increasing passenger numbers, it has clearly failed to meet its prime objective of reducing rail’s cost to the taxpayer. Moreover, the graph shows that after British Rail (BR) introduced sector business management in the early 1980s, rail’s cost to the taxpayer was reduced by 46% between 1985 and 1993.
One of the reasons for this is that, at that time BR introduced the business profit centres. The impact of this is illustrated by our feature on how 125mph track renewal handbacks were achieved on the East Coast Main Line in the mid-1980s. While this was an impressive achievement by the engineers concerned, it was only possible because the BR Inter-City director authorised expenditure on nine dynamic track stabilisers as he considered that the resultant reduced journey times would generate additional revenue.
Although spending money to make money in this way is a basic business practice, Government does not apply this philosophy to the rail network. Currently, the Treasurer receives passenger revenue while the Department for Transport is responsible for cost control. Network Rail CEO Andrew Haines has described this arrangement as “evil”. It is to be hoped that Great British Railways will see the reintroduction of profit centres at an appropriate business level.
In recent times, there has been significant increases in the cost of infrastructure projects as highlighted by HS2 and costly electrification projects. For example, the original 12km Docklands Light Railway opened in 1987 at a cost of £217 million in today’s prices.
As shown in the table, the Scottish Airdrie to Bathgate and Border projects each delivered a substantial amount of infrastructure for respectively £520 and £612 million at today’s prices. Our website has a feature about these projects which considers, with some justification, that these Scottish projects are amongst the most cost effective rail projects delivered since privatisation. Our feature on the Railway Industry Association (RIA)’s annual conference shows how high rail project costs are a real concern that threaten future rail enhancements. It is important to understand why costs are so high and how projects can be delivered at an affordable price. Hence, we would strongly suggest that previous cost-effective projects, such as these two Scottish projects, are benchmarked to learn the lessons from them.
Our feature ‘implementing cost effective electrification’ describes the work done to reduce the number of structures that need to be rebuilt for electrification projects, provide risk-based standard and simplify electrification approvals. These worthwhile initiatives will only bear fruit with the steady stream of electrification work that the network requires.
Peter Stanton’s feature on the PWI electrification conference includes an explanation of how the delivery of electrification in Germany is the subject of a performance and financing agreement. Among other topics, this event also considered a proposal to extend DC third rail electrification.
As part of our light rail focus, Paul Darlington describes Australia’s biggest public transport project, the Sydney Metro, which is building 113km of new metro rail that will be operated by driverless trains. Closer to home, Rail Engineer visited the Very Light Rail (VLR) innovation centre in Dudley for a progress update on the Coventry VLR system. This feature also reports on the Revolution VLR which has been tested at Ironbridge.
The eight tram systems in the UK and Ireland use seven different grooved rail sections in their embedded street tracks which total just over 100km. Malcolm Dobell explains the subtleties of embedded rails and the benefits of standardising these grooved sections. Back to heavy rail, the railways of Southern England have 5,200km of track and carry 1.6 billion journeys each year. Clive Kessell reports how a RIA Unlocking Innovation event considered innovations that could help meet the challenges of operating such a heavily trafficked railway.
Forty years ago, a signaller at Carlisle Power Signal Box noticed that his panel showed a divided freightliner train. He switched the rear portion away from Carlisle station onto the Goods Avoiding Line where it crashed to produce significant wreckage, though no-one was hurt and there was no service disruption. We explain why this accident occurred and how its lessons are still relevant.
We also describe the recent fatal collision at Talerddig in Wales on which the Rail Accident Investigation Branch (RAIB) reported low levels of wheel/rail adhesion. Yet understanding all the factors that led to this tragic event must await RAIB’s report.
Wheel/rail interface is a complex and persistent problem. As we have reported, the ADHEsion Research challenge (ADHERE) has led various low adhesion initiatives. This month we report on a trial that successfully demonstrated how machine vision can analyse high-resolution images from forward-facing cameras to identify areas of low adhesion. We also report how RSSB is developing a model to evaluate rolling stock and infrastructure design features to guide trains when they are derailed as part of the development of a derailment mitigation strategy.
Rail Engineer was recently in Berlin to attend the biennial InnoTrans event. This is the world’s largest rail marketplace at which over 2,900 exhibitors in 42 halls promote their products. Our overview of this event gives an indication of its scale and variety and shows why this is a must-see event for anyone wishing to see the scale of the worldwide rail industry.
An important new addition to the UK’s rail industry is the Siemens Mobility’s rail manufacturing plant in Goole. Matt Atkins was there when this plant opened on 3 October. As he reports, this plant will assemble 80% of London’s new Piccadilly line trains and all future Siemens trains for the UK with the first Goole-assembled train expected to be completed in Spring 2025.
The rail industry is essentially its people who need to be nurtured and developed. This was Iain Rae’s key message in his address as the new chair of the IMechE’s Railway Division (RD). In this, he emphasised the importance of diversity and inclusion and used his own experience to offer advice to young engineers about their development. He also exhorted those with influence to develop future rail engineering leaders.
This is certainly a message that Rail Engineer supports.
At around 19:26 on the evening of 21 October 2024, train 1J25, the 18:31 Transport for Wales (TfW) passenger service from Shrewsbury to Aberystwyth, collided with train 1S71, the 19:09 Machynlleth to Shrewsbury passenger service, also operated by TfW. The trains collided approximately 800 metres west of the passing loop located at Talerddig, Powys on Network Rail’s Cambrian line. Very sadly, one passenger died and four other people were seriously injured. Eleven more people sustained injuries which required hospital treatment.
Image credit: RAIB
In addition to emergency services carrying out rescue operations, British Transport Police, the Office of Road and Rail (ORR) and the Rail Accident Investigation Branch (RAIB) have commenced investigations. This note is based on bulletins issued by RAIB. On the day after the collision, RAIB issued a statement reporting that its “…initial inspection of the track on approach to the point of collision found evidence that wheel/rail adhesion was relatively low, suggesting that the train may have entered into wheel slide when braking.”
On 5 November 2024, RAIB issued an update following its examination of the site and the trains involved. The trains were both two-car Class 158 diesel multiple units. These units are equipped with wheel slide protection systems and fixed rate automatic sanding systems, which discharges sand to the track when wheel slide is detected during braking, a system which aims to increase the available friction at the wheel/rail interface in poor adhesion conditions.
The railway approaching Talerddig from each direction consists of a single track. At Talerddig itself, there is a passing loop. Eastbound and westbound trains were timed to pass each other, stopping in the loop if necessary. Westbound trains climb an ascending gradient to enter the loop and, on exiting, rejoin the single track as it descends towards Llanbrynmair and Machynlleth.
The Cambrian line is equipped with the European Train Control System (ETCS), the signalling and train protection sub system of the European Rail Traffic Management System. This system has no lineside signals and transmits speed and movement authority into the train, displayed to the driver alongside the train’s speedometer. The limits of each section of track controlled by the system are signified by reflective lineside signs known as block markers. The train driver’s display would show if a train were required to stop at a block marker. The block marker itself acts as an absolute position location and back up in the event of a failure.
RAIB’s preliminary examination has found that westbound train 1J25 had been due to stop in the loop at Talerddig to allow eastbound train 1S71 to pass. Initial analysis of data from 1J25’s on-train data recorder (OTDR) showed that the driver applied service braking to slow the train as it neared the loop at Talerddig. Around 40 seconds after the first service brake application, the OTDR records an emergency brake demand being made. This emergency brake demand remained in place until the collision. OTDR data shows that wheel slide started during service braking and was constant during emergency braking.
Image credit: RAIB
Train 1J25 entered the loop at Talerddig and, although it slowed while passing through the loop, it did not stop before passing the block marker positioned near the exit. The train left the loop, rejoined the single line, and continued to travel for approximately 900 metres on the descending gradient, before colliding with train 1S71.
RAIB reported that there is conflicting evidence relating to the speed of the trains at the point of collision. Initial analysis indicates that train 1J25 was travelling at between 24km/h (15mph) and 39km/h (24 mph), while train 1S71 was travelling at around 10km/h (6mph) in the opposite direction (a closing speed of up to 49km/h (31mph). RAIB is continuing to analyse evidence relating to the collision speed.
Building on the earlier statement, having carried out measurements of wheel/rail adhesion levels at various locations from the approach to Talerddig loop to the point of collision, RAIB reported that levels of wheel/rail adhesion were low.
In addition, RAIB’s inspection of the automatic sanding system fitted to train 1J25 after the accident showed that the sanding hoses of the active sanders on the leading vehicle of this train were blocked and apparently unable to discharge sand.
It would be wrong to assume that the collision was caused simply by poor adhesion and blocked sander hoses. These may well be the immediate causes, but, as was seen from RAIB’s exhaustive investigation into the collision at Salisbury in 2021, there are likely to be many causal and contributory factors. The circumstances of both collisions appear to be superficially similar, but we will have to await RAIB’s report to understand all the factors that led to this tragic event.
The Permanent Way Institution’s annual electrification conference was attended by around 150 delegates and was opened by its president, Mona Sihota. While there remains uncertainty about future electrification, both the Midland Mainline and the Transpennine Route upgrades are well underway, and existing electrification assets (which power around 80% of UK rail vehicle-km) need to be maintained, renewed, and enhanced to cope with climate change and traffic growth. The level of Network Rail funding agreed for 2024-2029 (Control Period 7) makes using technology to reduce equipment lifecycle costs ever more critical.
The conference welcomed expert speakers from a range of electrification disciplines and organisations. They focused on technologies that are already enabling cost reduction and would highlight good practice across the UK and continental Europe.
The conference was launched by Lord Patrick McLoughlin who was Secretary of State for Transport from September 2012 to July 2016. He considered this to be a “Wonderful job with difficult times!” He recalled the significant rail industry renaissance prior to the Covid pandemic and viewed the new political appointments for transport as being encouraging for the future, particularly the appointment of Lord Peter Hendy as Rail Minister.
Considering the question of “What is Rail for?”, he felt that rail had a vital part to play in promoting economic growth and regeneration. Cancelling a large portion of HS2 reduced the positive impact of the southern portion south of Handsacre, yet the current scheme had still added around £10 billion to the economy of the West Midlands. It was a matter of regret that too much emphasis had been placed on HS2’s speed rather than its real purpose of releasing significant extra capacity on existing routes.
Image credit: iStockphoto.com/MarcScrutton
He felt that the appointment of ‘Metro Mayors’ could have a significant impact on transport planning and investment with a focused understanding of local requirements and preferences, more effectively directing investment. The ability to complete the implementation of Great British Railways would bring a “guiding mind” for the industry and allied to that, the development of technology could drive lower costs.
While responding to questions, Lord McLaughlin felt that there was a need to understand that a railway was a “whole system”, and the audience appreciated his view that a “rolling programme of electrification” was required. Overall, the conference was glad to hear from someone who will bring the experience of senior political office to play in his new role in Transport for the North.
Third rail extension
The first technical presentation considered extending DC third rail electrification. The presenter was Tom Wong, Network Rail’s assistant electrification and plant maintenance engineer for the Sussex Route.
Historically, the pre-nationalisation Southern Railway concentrated on third-rail DC electrification as, in early days, on-board rectification was not easily practicable, and it provided a simple traction current feed to DC traction motors. This was last extended into South Hampshire in the late 1980s. Other than some minor installations the expansion of the conductor rail system then stalled and tended to be discouraged by various agencies. These left pockets of diesel traction with the associated environmentally unfriendly emissions and a lack of flexibility in the use of electric rolling stock.
Tom explained the advances which had been made in engineering the contact system and its associated operation and maintenance. Hybrid traction and energy storage were mentioned but the emphasis was also on safety for the passengers and the public. Proposals included switching the voltage on the conductor rail in platforms to be live only when a train was present. Protection for the workforce had been enhanced by the development of negative short-circuiting devices to bond the conductor rails.
Tom anticipated that acceptance might now be gained to fill in the gaps in electrification and eliminate diesel working. The Uckfield line and west of England routes were cited as worthy candidates to gain fixed electrification. Tom finished with the neat statement: “An electrified Railway is a better railway, no matter how that is achieved.”
Alternative traction
Alternative traction energy sources were considered by Zhongbel Tian, assistant professor in Transport Energy Systems at the University of Birmingham. He noted that the Network Rail traction decarbonisation network study predicts that to achieve the end of diesel-only traction by 2040 and net zero by 2050, some 13,000 single track kilometres (STK) would require electrification with over 1,300 STKs for hydrogen train deployment, over 800 STKs for battery train deployment while there are 300 STKs where a technology choice has not yet been made.
He noted that for lines with low traffic density, it is difficult to make a financial case for electrification. For such lines, Battery EMU trains are suitable for decarbonising short-distance routes with low traffic density, while Hydrogen EMU trains are suitable for decarbonising long-distance routes with low traffic density.
Image credit: Network Rail
German electrification
Rudiger Stolle, head of engineering at Powerlines Group, provided the conference with a European perspective. Within the UK, around 38% of the system is electrified whereas in Germany the figure is around 60%. He stressed that efficient electrification projects need a constant level of funding to develop and retain well-experience engineering and project management teams, as well as a fleet of specialist electrification plant and equipment.
In Germany, politicians now recognise that due to the lack of funding from the early 2000s, there is now a requirement to renovate 4,229km of track which will be done by a series of route closures with associated diversions. This work is the subject of a 2019-29 funding agreement which allows for more robust long-term planning. In addition, since 2009, a performance and financing agreement between Deutsche Bahn and the German government funds ‘replacement investment’ which accepts that maintenance costs fall as old electrification assets are replaced.
Rüdiger explained how Powerlines was constantly investing to ensure the retention of technically competent design and construction teams. Closing his presentation, he made the point that individual companies can only do so much as government intervention is needed to ensure a steady flow of work for the supply chain.
After the first period presentations there was a change of pace. To avoid a day-long continuous flow of slide-related presentations, the conference then split into three breakout sessions which considered: DC conductor rail technology developments; electrical systems with static frequency converters for traction supplies; and catenary systems at bridges. These three sessions gave rise to active and high-quality debate and offered the opportunity for greater delegate engagement.
RSSB research
The afternoon sessions commenced with a presentation on the Rail Safety and Standards Board’s (RSSB) Research programme by Edordu Chibuzor, principal energy engineer, and Mark Hanham, senior research analyst, at RSSB. The title was ‘Feasibility of Smart Traction Energy management on the Western Route’. Mark spoke about the role of RSSB and its importance in acting as a collaborator in bringing various groups together to help solve problems.
This particular research project involved representatives from Network Rail, First Great Western, First Group, and Hitachi, with RSSB acting as the facilitator. It considered power demand management across Western Route in real time and, through various modelling exercises, aimed to understand how power can be efficiently delivered across the route. To date, the theoretical work has shown multiple benefits in managing power demand in this way at both train and system level operation.
OLE asset management
In her presentation, Ellen Wintle, Network Rail’s infrastructure director – West Coast South Route, explained her views on Overhead Line Renewals and Maintenance. She first reminded her audience of the definition of asset management which is “the balancing of costs, risk and performance to achieve an organisation’s objectives.”
Image credit: iStockphoto.com/Sterling750
Achieving this requires a strategy with guidance for the various asset types considering their renewals, refurbishments, and repairs as well as inspection and maintenance activities. These activities need to be planned in the light of safety requirements, the age of the asset, and the utilisation of the asset such as line speed and pantograph passes. The control period seeks to maximise the funding available over a greater asset base. A key theme is greater life extension works and campaign changes with less full wire run renewals.
Ellen’s team has also started to look at smarter ways of working, for example Risk Based Maintenance (RBM) is now applied to OLE assets, which allows for alternative inspection regimes to tradition practices. This is supported by using emerging technologies such as AIVR, Drones, PANDAS, and OLE StAT to investigate issues. The intention is to enable maintenance teams to concentrate on removing high risk defects on the rail infrastructure as well as providing faster response times. This is particularly important for circuit breaker operations which are one of the biggest causes of rail disruption.
Noting that track access is at a premium, with a five- or six-hour possession typically allowing two to three hours machine working time once boards have been put out and switching and earthing completed. Ellen made a plea for designers to consider the workforce during early design stages to consider location of road rail access points and earthing points.
She spoke about the Control Period 7 settlement which for her route was broadly £800 million capex and £650 million opex and she stressed the need for every pound spent to achieve the best value. This requires route asset managers and engineers balancing requirements of the policy, local operational demands, and competing risks within the funding available.
Towards the end of her presentation, Ellen showed an absorbing video which stirred memories of some working practices from past decades which included the alarming process of walking along the top of a moving train attaching droppers. Ellen finished her presentation by posing the question of how we can come together within the industry, stating: “We all play a part in moving our industry forward – whatever our roles!”
To conclude
The last session of the day was a panel Q&A discussion. There was enthusiastic reaction to the news that Network Rail is developing plans for a proposed extension of the DC third rail network south of the Thames. Issues of electrical clearance and discontinuous electrification generated some lively questions with overwhelming support for cost effective solutions developed in the Valleys scheme and the Midland Main Line. With a spontaneous round of applause, the conference loudly endorsed a panel call to arms to reject risk averse attitudes and adopt best practice innovations and proven European solutions without elaborate, time consuming, and costly trials.
Paul Hooper, technical director at AtkinsRéalis, rounded off the day by highlighting the valuable insights from influential industry experts. He particularly welcomed the inclusion of DC third and fourth rail systems on the agenda, and the inclusion of a wider European perspective. He thanked all who had organised such a successful event and looked forward to the 2025 PWI Electrification conference planned for July in Cardiff.
In 2009, the Great Western Electrification Programme (GWEP) was estimated to cost £1 billion. By 2015 the cost had risen to £2.8 billion. As a result, the programme was cut-back in 2017 with no electrification to Oxford, Bristol, or Swansea. This also led to a negative government perception of rail electrification and that bi-mode traction was seen to be the way forward.
Network Rail CEO Andrew Haines’ response was that “we must not underestimate the harm done by the horrendous costs and schedule over-runs on the Great Western electrification. The ball is firmly back in our court to show that we can deliver cost-effectively, and that we can be trusted.”
In 2019, the Railway Industry Association (RIA) published its Electrification Cost Challenge report which described how many aspects of the design and delivery of GWEP had added costs. As an example, instead of using long-establish empirical design guidance, GWEP’s designers had taken a risk averse approach and designed the piles from first principles which resulted in much longer piles than expected.
Once this issue was recognised, Network Rail commissioned a research project undertaken by the University of Southampton which demonstrated the suitability of the empirical method. This research was the basis for Network Rail standard NR/L2/CIV/074 ‘Design and Installation of Overhead Line Foundations’ which became a mandatory requirement in March 2018.
Reducing electrification costs
Work to reduce electrification costs has been done as part of an ‘enabling efficient electrification workstream programme’ which was jointly convened between DfT and Network Rail in 2021. To understand how this work has progressed, Rail Engineer was glad to have the opportunity to meet Richard Stainton, Network Rail’s engineering expert (electrification) who explained that the cost for an electrification project can be broken down into three parts:
Route clearance – reconstructing bridges etc., or track lowering, to make space for energised overhead line equipment (OLE) and train pantographs.
OLE installation – labour plant and materials. (Materials make up between 3-5% of an electrification projects cost).
Other – Track access compensation, distribution, grid connections, signalling immunisation, de-vegetation, lineside fencing etc.
Richard considered that the biggest opportunity to reduce the cost of electrifying a route is reducing the volume of route clearance works. Therefore, a considerable amount of work has been done to provide evidence that the physical space required for electrical clearances can safely be reduced.
Cardiff Intersection Bridge.Surge Arrestor.
Although clearance was the main focus, the efficient electrification workstream programme has considered many other issues in an incremental approach that offered marginal gains over a wide range of issues was needed. To illustrate this, Richard produced a mind map that had eight categories with a total of 37 initiatives.
Although most of these related to electrical clearances others included:
Bridge parapets – securing widespread adoption of deriving parapet heights from risk assessment rather than a blanket application of 1.8 metres usings the risk assessment methodology specified in the NR/L2/ELP/27717 ‘Bridge Parapet Electrical Risk Assessment’ issued in March 2023.
OLE structure spacing – Following research on OLE wind loading by the University of Birmingham, NR standards have been changed to increase spacing between OLE structures from 65 metres to 95 metres to reduce the number of structures by an estimated 5%. This also offers designers greater flexibility to fit OLE structures around existing railway features.
Rationalising traction distribution principles to reduce the number and complexity of electrical substations with designs that use the best modern practice in electrical power switchgear and control architecture. For example, modern protection systems enable track sectioning cabins to be replaced by disconnectors which give savings of around £2 million per 20km.
Pantographs with inerters (a damper that resists force in proportion to acceleration) to improve the pantograph’s dynamic performance. This offers benefits that include reduced arcing and steeper wire gradients.
Insulated pantograph horns – at stations the pantograph horn is the item of energised equipment that is closest to passengers. Also, at arched bridges it is the closest energised equipment to the bridge. Insulated pantograph horns, if fitted to all trains, offer benefits that include avoiding the need to cut back station canopies and reducing the number of bridge interventions.
Reduced earthing and bonding – standard NR/L2/ELP/21085 previously required all conducting items that are located within 5.2 metres either side of track centre line to be bonded to traction return. This has been amended to everything within 30 degrees below the contact wire. As a result, the previous 5.2 metres distance has now been reduced to typically 3 metres to 4 metres from the track centre line.
Protective signalling gantry mesh – the requirement in Euronorms to use a small mesh size can result in significant wind resistance. Hence electrification may require rebuilding of the signalling structure. The standard will allow for a larger mesh size which still provides full protection without the significant increase in wind loading.
Ice – clearances used to allow for wire sag due to ice on the conductor were determined on the basis of the Electricity Commissioners’ Overhead Line Regulations from 1896. Using modelling techniques developed by the American Military, Network Rail has shown that the effects of ice on UK master series OLE falling below the minimum clearances is negligible. As a result, the environmental conditions that OLE designers are required to consider no longer includes sag due to ice. However, ice is still considered in respect of structural loading.
Under bridge clearances
Of all the cost saving measures considered, perhaps the one that has provided the most benefit is Voltage Controlled Clearances (VCC). VCC uses surge arresters and an insulating coating to reduce clearances under bridges to less than 63mm. With an allowance for a 43mm uplift, it was necessary to prove that it was safe to have a 25,000V bridge arm a mere 40mm below the bridge structure.
This clearance is normally governed by the need for the OLE to safely withstand voltage surges from arcing, switching harmonics, and lightning strikes which can exceed 100kV. Metal oxide surge arresters placed either side of a bridge ensure that the OLE under the bridge will not be subject to such surges and so needs only be designed for the maximum system voltage of 29kV. Under normal operation, surge arresters are open-circuit but have a low impedance during surges which then diverts the voltage surge through the surge arrester to earth.
The use of surge arrestors was first trialled on a high voltage test rig at the University of Southampton as described in Rail Engineer 190 (May-June 2021). They were subsequently fitted at Cardiff Intersection bridge to permit the route under the bridge to be energised in December 2019. This is a rail-over-rail bridge which would have otherwise required significant rebuilding costs. However, at such low clearance bridges it is essential that the track remains fixed in position. This is considered to be adequately managed by existing track management standards.
At this Cardiff bridge, the use of VCC saved an estimated £20 million pounds. Initial studies for future electrification schemes using the clearance methodology developed for Cardiff Intersection bridge indicates a reduction of more than 40% in the number of bridges requiring re-construction. This indicates that this VCC methodology has the potential to save hundreds of millions of pounds if there was to be a significant electrification programme.
To optimise this concept and further demonstrate its robustness, tests were undertaken in a high-voltage test laboratory in Budapest which was the only test house willing to build a ‘bridge’ in a high voltage test laboratory. This allowed the observation of 12,000 A fault currents for 300 milliseconds which is a far greater energy level than can be expected for typical short circuits.
Applying insulating coating.High voltage flashover during testing in Budapest.
NR/L2/ELP/27716
Many of the initiatives to reduce the cost of electrification concern electrification clearances, as specified in the 276-page Network Rail standard NR/L2/ELP/27716 ‘Electrical and mechanical clearances on overhead electrified railways’. This is essentially a manual and was issued in December 2023. It delivers the requirements of 13 different railway and British Standards as well as taking account of findings from the enabling efficient electrification workstream.
Its requirements are coded Red (no variations permitted), Amber (variations allowed subject to an approved risk assessment), and Green (use unless alternative solutions followed).
The first 22 pages introduces the four modules of this manual and refers to 92 reference documents.
The first module is a 97-page design specification for clearances. This considers the clearance between the three aspects of the OLE system which are: 1) OLE conductors; 2) OLE supports; and 3) Along Track Feeders (ATF) and twelve specific areas that might be impacted by the OCLS. These are:
Overline structures (e.g. bridges, tunnels).
Rail vehicle bodies.
Pantographs.
Signals.
Single phase HV cables.
Standing surfaces (non-restricted public access).
Standing surfaces (restricted lawful public access).
Standing surfaces (restricted non-public access).
Level crossings.
Vegetation.
Third party land.
Third party networks.
As a result, this first module defines the requirement for 22 types of static and dynamic electrical clearances as well as the requirements for the mechanical clearance between pantographs and overline structures.
As described later, a further module is a generic safety case for OCLS clearances. The third 50-page module provides the design input parameters and secondary calculations that are required for such matters as track fixity, rail vehicle kinematic reference profiles, pantograph sway, contact wire uplift, and wind speeds. The fourth and final 11-page module has tables which categorise the electrical insulation performance of clearances in 25 kV electrification systems.
Authorising new electrification
The Railways (Interoperability) Regulations 2011 require that no new subsystem (e.g. new electrification works) can be put into use on the UK rail system unless the Office of Road and Rail (ORR) has authorised its use. This requires a demonstration that the subsystem is technically compatible with the rail system and that it has been designed, constructed, and installed to meet the subsystem’s essential requirements.
The authorisation process requires the applicant to submit a formal safety assessment report which includes a common safety method risk assessment and certificates of verification by an independent notified body.
It would be reasonable to consider that new electrification work designed and installed in accordance with Network Rail standards is compatible with the rail system. Yet, the approval process requires that this be demonstrated from first principles.
As an aid to project teams, the second module of NR/L2/ELP/27716 has a generic safety case for OCLS clearances. This includes a system definition, lists of hazards, and methods that might be used to demonstrate the effectiveness of control measures such as surge arresters. It also provides bow tie diagrams (these show an accidental event in terms of its initial causes, negative consequences, and the barriers intended to prevent or control its associated hazards), a spreadsheet recording 55 hazards, and shows the OCLS and AFT design hierarchy.
Thus, this module of NR/L2/ELP/27716 provides a generic safety case that can then be cut and pasted into the safety assessment report to which a relatively small number of project specific issues are added. Hence the safety approval process for electrification projects, in effect, requires each project to demonstrate that Network Rail’s electrification standards are fit for purpose. It is not clear what purpose this serves.
Image credit: Network Rail
Retaining expertise
The work of the efficient electrification workstream has done much to address Andrew Haines’s warning that after GWEP, the industry has to be trusted to deliver electrification efficiently. Since then, much work has been done to provide the evidence that standards are fit for purpose and incorporate the findings of research done to reduce the cost of electrification.
As a result, GWEP’s design and construction issues have now been addressed. Yet there may well be scope to reduce off-site costs by, for example, reducing overheads and an improved contracting strategy. It is also clear that safety approval costs could be reduced. The 276 pages of NR/L2/ELP/27716 are a reflection of the complexity of electrification engineering and highlight the need for electrification work, such as much needed freight infills, to retain expertise in electrification design and construction. Without such projects expertise will be lost, so when electrification work resumes, as surely it must, new mistakes will be made, old mistakes will be re-made, and costs will be high.
It should be self-evident that the most reliable way to minimise electrification costs is a stable, long-term electrification programme that builds-on and retains the skills and experience necessary to deliver it effectively.
The GWEP electrification programme illustrates this point. It started after there had been no new electrification for 20 years. When it became apparent that some of its OLE mast piles were designed to be three times longer than those used on previous schemes, it should have been apparent that this was a hugely expensive mistake. Yet there was no-one in authority with electrification experience who could halt the use of such piles.
At the RSSB sponsored Vehicle/Track System Interface Committee seminar, RSSB’s Dr David Griffin and University of Huddersfield’s Dr Philip Shackleton explored how the industry might explore additional measures for the guidance of derailed trains. This work was commissioned to follow up a recommendation from the RAIB investigation into the Carmont accident in August 2020 (recommendation 12 – see panel).
In the Carmont accident, a train derailed on debris washed from the side of a cutting. In 2016, a train derailed in a similar way just north of Watford tunnel.
The outcomes were very different and could have been a lot worse. Carmont happened during the pandemic emergency when there were few people on the train. Although three people sadly died, given the nature of the subsequent damage, a more crowded train would have resulted in a lot more casualties. At Watford, the train derailed into the six foot and was partially constrained when one of the running rails became sandwiched between the traction motors and/or gearboxes on the leading motor carriage. Although another train was approaching, the driver managed to send a code red alarm over the radio causing the driver of the approaching train to apply the emergency brakes before hitting the derailed train with a ‘glancing blow’ at comparatively low speed. These two examples highlight those two derailments, with a very similar cause, had quite different outcomes.
The research project, ‘Assessing the case for rolling stock and infrastructure design features that can provide guidance to trains when derailed’ (T1316) involves two strands.
Site of Carmont derailment. Image credit: RAIB
Firstly, building on the comparison between Carmont and Watford, RSSB is developing a risk model to understand the benefits of derailment containment measures. It is assessing both location and route-specific derailment risks accounting for the features of the line of route, rolling stock, operational speeds, the operational environment, and passenger use. Using this work, the risk benefit from rolling stock and infrastructure upgrades can be assessed. It can also be used to provide cost benefit results for new lines, upgraded lines (renewals) and measures to address specific high-risk locations. This is a significant undertaking. The overall risk model combines four models: causal, trajectory, escalation, and loss.
The causal model calculates the probability of derailment in each 25-metre section, covering approximately 40 derailment causes. Probability is dependent on the assets present at the location (cuttings, level crossing, etc.) and train type (passenger, freight). It has been grouped in eight derailment types:
Derailment on facing points (e.g., Potters Bar, Grayrigg).
Derailment due to broken rail on a curve (e.g., Hatfield).
Derailment at leading wheelset caused by striking a major obstruction (e.g., Ufton Nervet, Great Heck).
Derailment of leading wheelset – not a major obstruction (e.g., Carmont, Watford).
Non-leading wheelset – major rolling stock or track failure resulting in loss of support such as broken rail or failed bearing (e.g., Newton Abbott).
Non-leading wheelset – Minor rolling stock failure or track failures where there is not a loss of support, such as gauge spread or track twist (e.g., recent incident at Grange-Over-Sands)
Rail vehicle(s) roll-over due to overspeeding (e.g., Morpeth)
Roll-over due to severe storm
The Trajectory Risk Model calculates the path of the derailed train for each derailment type – based on speed, curvature, and presence or otherwise of switches and crossings, but does not consider the effect that collision with structures, earthworks etc. has on the path of the derailed train.
Derailment mitigation will impact the trajectory.
The Escalation Model calculates the possible escalation of the derailment such as collision with structure, vehicles roll-over/fall, collision with another train, or fire/explosion. The event tree structure with probabilities is based on the Trajectory Risk Model.
And finally the Loss Model calculates the loss (safety/cost) for the base derailment plus any escalations from the Escalation Model. So far, the principles of the model have been created with a small number of sample sections. Results for Carmont were illustrated for derailment risk, likely consequences and weighted fatalities index.
Next steps are to extend the model to the national network (approximately 600,000 25-metre sections) together with train types operating on each section, to incorporate Huddersfield’s work on the effectiveness of derailment mitigations (below) and the development of a simple user interface. Rail Engineer thinks this is a great deal of work to be delivered by the stated Autumn 2025.
The University of Huddersfield is simulating vehicle track interaction during the in-line phase of a derailment, post derailment containment including negative interactions e.g. with switches and crossing (which tend to make the outcome worse) and a parametric study on effectiveness of derailment containment for various operating conditions. The idea is that the model can be used to assess train or track features that might prevent trains deviating from plain line in the event of a derailment. But the first challenge is to build a modelling environment in which these features, or newly designed features can be evaluated.
Simpack-Rail was used to model up to the derailment point. This has the benefit that existing models could be used. Specific models were created in generic Simpack – the general-purpose multi-body dynamics package. Rails, guard rails, sleepers and ballast were modelled. The results of simulated trains running on sleepers/ballast were compared with published material on simulated and measured wheel response. The simulation had to consider wheel/ballast interaction including:
Initial geometry – nominal profile, 3D geometry.
Ballast surface deformation – non-linear force-deflection curve for a nominal wheel and inertial reaction from displaced ballast mass.
Energy dissipation (longitudinal & lateral) – penetration depth and ballast characteristics and friction resistance from ballast displacement.
Guidance effects – lateral reaction force (for the wheelset), inertial reaction force from ballast displacement, and friction sliding of wheel and ballast displacement.
It also allowed contact with submerged bodies/faces such as sleeper ends especially for duo block sleepers and there is provision for other surface types to be added later.
So far, the work has demonstrated that the simulation is feasible. The next steps move onto exploring post derailment mitigations, namely: (i) assessment of negative interaction of mitigations such as vehicle mounted and track mounted mitigations and vehicle mounted mitigations at switches and crossings; and (ii) application of the developed modelling capability into the derailment risk model.
The description above makes the modelling sound easy, but the speakers described their work as “pushing the bounds of modelling”.
RAIB Carmont Report recommendation 12:
“The intent of this recommendation is to take account of learning from the Carmont accident in the development of a coherent long-term strategy for derailment mitigation. It is anticipated that implementation of this recommendation will be informed by work, including RSSB project T1143, already undertaken by the rail industry as a result of recommendation 3 of RAIB’s investigation of the Watford derailment.
“RDG and Network Rail, in conjunction with RSSB, should consider and incorporate all relevant learning from the Carmont accident into the assessment of rolling stock and infrastructure design features that can provide guidance to trains when derailed. Particular features to be taken into account include:
The risk of derailment from relatively small landslips and washouts.
Position of track relative to adjacent ground on which derailed wheels may run (that is, features that can affect the deviation of a derailed train).
Proximity to features with the potential to increase the consequence of an accident (bridge parapets, tunnel portals etc).
Topography likely to increase the extent of vehicle scatter.
The above-mentioned assessment should then be used to develop a systemic, risk-based strategy for the provision of additional measures for the guidance of derailed trains that takes into account the appropriate balance between infrastructure-based mitigation and vehicle-based.”
