London Gatwick Airport has taken a significant step in advancing its long-term growth plans by appointing 16 expert design firms to a refreshed design services framework, marking the start of a new chapter in its capital investment strategy. The newly established framework is designed to accelerate the delivery of design work across the airport’s upcoming projects by enabling faster engagement of consultants under pre-agreed terms. It spans a broad range of specialisms including architecture, civil and structural engineering, baggage handling systems, and fire safety engineering. Structured across five key lots, the framework includes both large and small multi-disciplinary teams to ensure flexibility and expertise across every scale of project. The selected firms include a mix of global engineering giants and innovative SMEs, reflecting Gatwick’s ambition to blend experience with agility. Firms appointed under the Large Multi-Disciplinary lot include Arcadis, AtkinsRealis, Baker Hicks, Jacobs UK, Ramboll, and WSP UK. The Airfield category sees AtkinsRealis, Jacobs UK, Ramboll and WSP UK return, while the Baggage lot welcomes IDOM, Principal Projx, Typsa, and Vlogix. Supporting innovation and diversity, the Small and Medium Enterprise (SME) Multi-Disciplinary lot brings together Hulley & Kirkwood, Lyndon Goode Architects, Pascall & Watson, Pellings, Pod Architects, and Webb Yates. Meanwhile, Jacobs UK and WSP UK have also been appointed under the Fire Engineering lot. Alasdair Scobie, Capital Programmes Director at London Gatwick, commented:“This refreshed design framework is a key enabler for delivering London Gatwick’s ambitious capital investment plan, ensuring high quality design incorporating more sustainable solutions delivered through a capable and competitive supply chain. “This is the first step in a broader construction supply chain strategy as we bring in the best designers, consultants and contractors to support the airport’s growth. It’s a crucial time for us, and we’re excited to begin this next phase in partnership with such a strong and diverse team.” The announcement underlines Gatwick’s commitment to sustainability, smart design, and inclusive development as the airport continues to evolve to meet future travel demands and customer expectations. Building, Design & Construction Magazine | The Choice of Industry Professionals

Contractors building HS2 have completed work on a pair of innovative extensions to the southern portal of its longest tunnel to eliminate the possibility of ‘sonic boom’ being created by high-speed trains entering at 200mph.  The structures, built at the southern end of the railway’s 10-mile Chiltern Tunnel to the north-west of London, are near identical to those now under construction at its northern portal in Buckinghamshire.  All trains entering tunnels anywhere in the world force air forward, creating pulses of energy that roll along the tunnel causing a small release of air pressure into the outside world at the far end. Known scientifically as ‘micro pressure waves’, they are inaudible on conventional railways. But in high-speed rail tunnels, air shoved forward without escape routes can create powerful pressure waves that emerge as an audible ‘thud’ or ‘sonic boom’. In a first for the UK rail network, HS2’s design includes extensions on all eight tunnels where trains enter at speeds above 140mph.  However, the length, physical setting and aesthetic of those at each end of the line’s tunnel beneath the Chiltern Hills mark them out as unique even to HS2. HS2 Ltd chief engineer, Mark Howard explains, “The maximum speed of HS2 varies along the route. But where the train is entering a tunnel travelling above 140mph we are building portal extensions to prevent ‘sonic boom’ occurring.  Although there are several tunnels on the line where train speed will be higher than in the Chiltern Tunnel, no other combines speeds of 200mph with length of 10 miles.  Its these unique physical characteristics that demand unique structures at each end.” First identified in 1974 during train testing on Japan’s then new 187mph ‘Sanyo’ shinkansen line, when people nearby noticed ‘booms’ near tunnel exits, the problem was solved by the invention of perforated portals extending from the tunnel entrance. Later, as train speeds gradually increased and further slight improvements in the control of micro-pressure waves were required, the solution was to radically enhance the train’s aerodynamics rather than retrospectively adding the pressure-dissipating portal extensions to tunnels that had already been built. The famous super-sleek, elongated aerodynamic snouts of Japanese high-speed trains cause the pressure to build up more gradually when the train enters a tunnel.   Building on over 40 years of research by the international rail community, the engineering team from HS2 Ltd, engineering consultancy Arup together with the University of Birmingham and Dundee Tunnel Research, developed and laboratory-tested HS2’s tunnel portal design. To mitigate against ‘sonic boom’ HS2’s tunnel beneath the Chiltern Hills requires bespoke portal extensions. Protruding up to 220 metres – around the length of two full-size football pitches – from a chalky cutting near the M25 motorway, they are each punctuated along one side with ventilation portholes. These enable some air pushed forward by the train to escape, making the pressure increase more gradual so that the micro-pressure wave emitted from the other end of the tunnel is undetectable. The basic design can be adapted to different lengths: the longer the extension, the weaker the micro pressure wave. In order to decide how long each extension needed to be for every HS2 tunnel, the team used micro-pressure wave measurements from Britain’s first high speed line between London and the Channel Tunnel, HS1 as the benchmark. The line’s tunnels do not experience sonic boom because the micro pressure waves are too weak. Therefore HS2’s research team used it as the basis to develop anti-sonic boom porous tunnel extensions for the new London-West Midlands high speed line. Mark added, “HS2 was designed from the ground up as an entirely new and complete rail system. This enabled us to develop all its constituent parts e.g. trains, tunnels, stations, power systems to complement each other and operate as intended. “In the case of avoiding sonic boom at tunnel portals, we used already-established key criteria including train speed, tunnel diameter and length to develop tunnel portal extensions that would prevent sonic boom occurring.” Commenting, Arup Fellow Richard Sturt said, “Arup is proud to have helped create a new international benchmark for the suppression of sonic booms with the HS2 tunnel portals. They are longer than any existing portals anywhere else in the world as we have prioritized seating capacity on the train, avoiding the need for a long nose section on the train like the Japanese shinkansen.  The portals’ unique tapered design combined with the precision-sized holes provide an incredibly smooth build-up of pressure as the train enters the tunnel. As a result, there won’t be any audible noises from micro pressure waves, despite the extremely high train speeds.” Construction of the Chilterns Tunnel, and its portal extensions was led by HS2’s main works contractor Align JV – that includes Bouygues Travaux Publics, Sir Robert McAlpine and Volker Fitzpatrick. The group finished building those at the southern end in January 2025, with the northern pair following in the autumn of this year. Once operational passenger trains will travel through HS2’s 10-mile Chiltern Tunnel in three minutes Building, Design & Construction Magazine | The Choice of Industry Professionals

The UK’s largest road infrastructure project in a generation has been given the green light, as the Secretary of State for Transport grants development consent for the Lower Thames Crossing. The ambitious scheme, connecting Kent, Thurrock, and Essex, is set to ease congestion at the heavily burdened Dartford Crossing. A Game-Changer for UK Roads Spanning 23km, the project includes twin tunnels stretching 4.2km beneath the River Thames, providing a vital new link between the A2/M2 and the M25. Designed to tackle severe congestion at Dartford—the busiest river crossing in the country—the Lower Thames Crossing is expected to improve traffic flow and unlock economic growth across the South East. The estimated cost of the scheme is £9.4bn, with the government exploring private finance options that could push the total to £10.2bn. Already, £1.2bn has been invested, with much of it allocated to the project’s extensive planning and approval process—the largest development consent order (DCO) application ever submitted in the UK. Following its initial submission in October 2022, the project underwent an exhaustive public examination before receiving approval on 20 March 2024. The decision, which had been delayed multiple times, marks a major milestone in one of the UK’s most complex infrastructure projects. Construction could begin as early as 2026, with completion expected in the early 2030s. In the meantime, project teams will work closely with local authorities and stakeholders to refine design elements and minimise community and environmental disruption. A Sustainable Approach to Infrastructure The Lower Thames Crossing is being positioned as a carbon-neutral construction “pathfinder” project. National Highways aims to significantly cut emissions by up to 70% through the use of low-carbon materials and alternative fuels, such as hydrogen. These sustainability efforts are expected to set a benchmark for future large-scale infrastructure developments, with potential applications in sectors like rail and nuclear energy. Beyond its transport benefits, the scheme includes major environmental commitments. Plans include the creation of six times more green space than the road itself, planting one million trees, establishing a community woodland, and developing two new public parks with Thames views. Nearly 5km of new and upgraded pathways will also be introduced for walkers, cyclists, and horse riders. Designed with extensive public consultation, several adjustments have been made to mitigate the impact on local communities and ancient woodlands. These include increasing lane capacity to three in each direction and extending the tunnel length. Creating Jobs and Boosting the Economy The project is expected to generate thousands of jobs within the construction sector, with a commitment to recruiting nearly half of the workforce locally. Skills training and employment opportunities will be a key focus, ensuring long-term benefits for communities in the region. To deliver the project, three main works contracts have been awarded: Industry leaders have widely welcomed the approval, calling it a transformative investment in the UK’s infrastructure. Balfour Beatty’s divisional CEO for major projects, highways and ground engineering, Phil Clifton, stated that the project would “unlock capacity, capability, and careers.” Skanska UK’s executive vice president Andrew English added that it would relieve congestion while showcasing innovations in low-carbon construction. Calls for Funding Clarity Despite the approval, there are concerns over the project’s funding. The Civil Engineering Contractors Association (CECA) has urged the government to make a swift decision on financing to ensure work can begin without further delays. However, not everyone supports the scheme. Green Alliance policy adviser Rosie Allen has criticised the government’s approach, arguing that investing in public transport and freight solutions would be a more effective long-term strategy. Campaign group Transport Action Network has described the decision as “economic madness,” questioning the viability of spending up to £16bn on a single road project at a time of budget constraints. As debates continue, the Lower Thames Crossing remains a landmark infrastructure project with the potential to reshape transport in the South East while setting new standards for sustainability in construction. Building, Design & Construction Magazine | The Choice of Industry Professionals

The Prime Minister recently announced the latest tranche of funding for the Transpennine Route Upgrade (TRU). This additional investment of £415m will enable further progress on the multi-billion-pound programme, ensuring the delivery of faster, more frequent, and greener rail services between Manchester, Huddersfield, Leeds, and York. Beyond the transport improvements, TRU is unlocking significant social and economic benefits for the region. Thousands of jobs and hundreds of apprenticeships are being created, local businesses are benefiting from supply chain opportunities and the shift towards greener transport will reduce carbon emissions by up to 87,000 tonnes each year. James Richardson, Managing Director for Transpennine Route Upgrade, said: “The government’s continued support for TRU is a clear vote of confidence in the work we are doing, which is an enabler to releasing the economic potential of the North. This funding supports our onward journey to be truly transformational, delivering faster, more reliable rail services that connect people to jobs, education, and leisure opportunities. “By improving connectivity and increasing capacity, we are not only enhancing journeys for customers but also helping to drive up investment supporting more housing and more jobs and boosting productivity across the region.” The TRU programme is delivering: With this latest announcement, it takes the programme to £7.3bn of approved funding and moves TRU even closer to delivering a modern, high-performing railway, that better connects communities across the North. By enhancing capacity, reliability and sustainability, the programme is improving journeys for passengers, and strengthening the region’s economic future. As work progresses, this transformative Transpennine Route Upgrade will play a vital role in unlocking new opportunities, supporting local businesses and helping create a more prosperous and better-connected North for generations to come. Building, Design & Construction Magazine | The Choice of Industry Professionals

The project will drive growth by tackling long standing congestion and improving connectivity between the south-east, the midlands and the north The government has just given planning permission for National Highways’ A122 Lower Thames Crossing project. The most significant road project in a generation will drive growth – the priority in the government’s Plan for Change – by tackling long standing congestion at Dartford and improving connectivity between the south-east, the midlands and the north. For more than 60 years the Dartford Crossing has stood as the only road crossing across the Thames east of London, making it one of the country’s most vital trade routes that connects some of the UK’s busiest ports to the rest of the country. Today, it is used by far more traffic than it was designed for and acts as a bottleneck that causes delays and diversions that holds back the country’s economy. The Lower Thames Crossing is a 14-mile new A-road that will link the A2 in Kent with the A13 and M25 in Essex through the longest road tunnel in the UK. It will ease congestion at Dartford by almost doubling road capacity across the Thames east of London, and make tens of millions of journeys quicker, safer and more reliable every year. The government is currently exploring private finance options for the project. Construction could start as early as 2026, with the new road expected to open in the early 2030s. The National Highways project is the first in a new generation of projects that will accelerate the construction industry’s move to net zero by using fuels such as hydrogen to power its construction fleet and only using low-carbon concrete and steel. This pioneering approach to carbon has cut the project’s estimated construction footprint by around half so far, with a target to achieve a 70% reduction. The new blueprint for low-carbon construction created on the project is already being replicated across other sectors ranging from nuclear and water to rail and aviation. The project will also restore nature across Kent and Essex by delivering six times more green space than road. Plans include one million additional trees, a new community woodland, and two new public parks overlooking the Thames. The project will also encourage active travel across the area by providing almost three miles of new or improved routes for walkers, cyclists, or horse riders for every mile of new road. The design of the new road was developed following a comprehensive programme of consultation with the local community and a range of organisations. Improvements made following feedback include future proofing it with three lanes in each direction along most of the route, reducing the impact on ancient woodland by 70%, and increasing the length of the tunnel to reduce impacts on local communities and the environment. Around 80% of the route now runs through a tunnel, cutting or embankment to blend it into the landscape and seven green bridges will blend the road into the landscape and provide safer crossing points for people and wildlife. “The Lower Thames Crossing is one of the UK’s most important infrastructure projects. It will unlock growth with quicker, safer, and more reliable journeys and redraw the blueprint for building major projects in a net zero future by scaling up the use low-carbon construction, and leaving a legacy of green spaces and green skills” Matt Palmer, National Highways Executive Director Lower Thames Crossing Matt Palmer, National Highways Executive Director Lower Thames Crossing, said: “The Lower Thames Crossing is one of the UK’s most important infrastructure projects. It will unlock growth with quicker, safer, and more reliable journeys and redraw the blueprint for building major projects in a net zero future by scaling up the use low-carbon construction, and leaving a legacy of green spaces and green skills. “Our plans have been shaped by the local community and refined by robust and rigorous examination from independent experts. We are more committed than ever to working with our neighbours to build the crossing in a way that offers them opportunities to work and learn new skills while reducing impacts. We are shovel ready and have our delivery partners on board, and today’s decision allows us to work with government on funding and start the detailed planning that will let us start construction as soon as possible.” During construction the project will give a boost to British jobs and skills by working with specialist suppliers from across the UK, and will employ almost half of its workforce locally, training them to build the Lower Thames Crossing and equipping them with the skills to take on future projects. Before main construction gets underway, the project and its three delivery partners will work with local authorities, landowners, and stakeholders to refine aspects of the design to further reduce the impact of construction on the local community and environment, and embed new and emerging low carbon technologies and materials. Over the coming months they will also carry out archaeological, ecological, and topographical surveys, as well as further ground investigations to prepare the detailed design and construction plans. Building, Design & Construction Magazine | The Choice of Industry Professionals

Following its 5-mile drive underneath the capital, HS2 lifted Tunnel Boring Machine (TBM) ‘Sushila’ out of the ground at the Green Park Way site in Greenford, West London. The cutterhead, front and middle shield, weighting 850 tonnes, were lifted from the vent shaft in one piece on Saturday, March 15, using a 750 tonne gantry crane. The TBM – with a cutterhead spanning 9.48 metres in diameter – was launched from West Ruislip in October 2022 and completed its journey in December 2024. TBM Sushila excavated over 1.2 million tonnes of earth and installed 4,217 tunnel rings. TBM Sushila was used to construct part of the Northolt Tunnel – an 8.4-mile tunnel being built by four TBMs which will take HS2 trains from Old Oak Common Station to the outskirts of the capital. Building, Design & Construction Magazine | The Choice of Industry Professionals

Island Line will fully reopen between Ryde Pier Head and Shanklin on Friday 2 May, in time for the Early May Bank Holiday weekend, following an intensive and complex programme of work to repair and refurbish Ryde Pier. The line between Ryde Esplanade and Ryde Pier Head has been closed since 6 September 2024 while Network Rail and South Western Railway (SWR) engineers have worked tirelessly to repair and preserve the historic Ryde Pier structure. Upgrades will make the pier and railway line more resilient to extreme weather, ensuring that services can continue to run safely and reliably for generations to come. Prior to the full reopening on Friday 2 May, the entire line from Shanklin to Ryde Pier Head will close from Saturday 26 April to allow engineers to complete final preparations for the resumption of services. During these six days, replacement buses will operate instead of trains. The works will include: Following this work, the line will reopen at the start of service on Friday 2 May, four days earlier than originally planned. The first service will depart Ryde St Johns at 05:23 and arrive at Ryde Pier Head at 05:29. The first train from Ryde Pier Head to Shanklin will depart at 06:03. Engineers will return to the line later this year to complete additional upgrades, replacing the rail between Ryde Esplanade and Ryde St Johns Road as well as the footbridge at Ryde St Johns Road. Further details about these upgrades will be announced in due course. George Murrell, Network Rail Wessex route renewals director, said: “I’m delighted that we’re going to be able to fully reopen the Island Line early and in time for the May Bank Holiday, which we know is a busy and important time for the Island’s tourism industry. “We’re now on the home stretch of this work and while I know it will be disappointing, we will need to close the line for the week preceding the resumption of services to finish the final pieces of work, safety checks and prepare the railway for the first service early on Friday 2 May. “I’d like to again thank passengers, residents and businesses on the Island Line for their patience and understanding while we’ve undertaken this programme of critical repairs and upgrades. “We look forward to the resumption of services on 2 May.” Mark Dunn, Island Line general manager, said: “Fully reopening Island Line on Friday 2 May, ahead of schedule and in time for the early May bank holiday, is fantastic news for customers and the Isle of Wight, particularly as we enter the busy tourism season. “The early reopening is due to the brilliant efforts of SWR and Network Rail colleagues, who have worked extremely hard since last September to make necessary repairs to Ryde Pier. “These repairs allow us to resume services from Ryde Pier Head station all the way through to Shanklin and will preserve the historic pier for many years to come. “We’re extremely grateful to our customers and Islanders for their patience while these important works were completed and look forward to welcoming them back for the full service soon.” Building, Design & Construction Magazine | The Choice of Industry Professionals

As cities are growing larger and with more cars on the roads than ever, the demand for better infrastructure increases. Roads and bridges are essential for our communities. They give us safe ways to do things like travel, daily commuting, and trade. The construction industry needs modern equipment to keep the community’s road infrastructure up to demand. Today’s machinery improves how quickly and precisely projects can be completed while improving the road’s sustainability. The Role of Construction Equipment in Infrastructure Development Infrastructure projects rely heavily on the efficiency and reliability of construction equipment. Machines like mini excavators, compact track loaders, and bulldozers are important in handling material, paving, and earth moving in road construction. They are able to handle different terrains and improve productivity. Mini excavators are great for bridge and roadwork as they fit in tight spaces while having strong power and accuracy in grading. This makes a mini excavator ideal in improving road infrastructure Ensuring efficiency in construction equipment is using high-quality parts and rubber-tracked equipment that provide stability and traction on various surfaces. Kubota, a leading brand in mini excavators and skid loaders can be recognized on many road infrastructure jobsites. Equipping these machines with good quality Kubota tracks improves traction and durability across all terrains. These machines can use many different attachments, which makes their skid steers and mini excavators very useful on any job site. Advancements in Road & Bridge Construction Machinery The construction industry has made great strides in technology that improve how we build. New tools like automation, GPS-guided machinery, and AI systems are changing the way we construct roads and bridges. For example, GPS-enabled grading systems help workers accurately level and excavate, which reduces waste and human error. Fuel- efficient and hybrid machines are also starting to be designed. These will lower emissions created by the construction equipment industry. Hybrid motors can cut costs by saving money in fuel usage. Smart telematics and remote monitoring systems give real-time data on equipment performance. This data can show where improvement and efficiency can improve on the site. The monitoring systems are also used for letting you know when maintenance is due; by keeping your equipment well maintained will reduce downtime. Together, these systems will boost productivity and safety with equipment and help keep road infrastructure within budget. Sustainability and the Future of Infrastructure Equipment The push for sustainability is changing the construction industry, including the machinery used for building infrastructure. Governments and industry leaders are promoting greener options to lower carbon emissions and reduce dependence on fossil fuels. Hybrid and electric construction equipment is becoming an eco-friendly alternative to traditional diesel-powered machinery. These machines create less pollution, make less noise, and use energy more efficiently. Manufacturers are also using biodegradable hydraulic fluids, recycled materials, and new design methods to make construction equipment better for the environment. By using sustainable practices and energy-efficient machines, infrastructure development is becoming more responsible and ready for the future, achieving economic and environmental goals. Challenges & Solutions in Modern Infrastructure Projects The construction industry faces many challenges in road construction, even with today’s technology. Challenges like the shortage of skilled workers, tight budgets, and never-ending regulatory compliances make it difficult. There is a strong demand for skilled road workers, but the workforce is not growing enough to keep up with the demand for infrastructure. Government budget caps can force worksite projects to choose cheaper solutions or contractors, which can affect the quality of the completed jobs. Having to keep up with regulations that are constantly changing can be difficult, but if not, it can result in fines or lead to a pause of the project. To help with these issues, training programs, and automation are helping workers gain the skills needed to operate modern equipment. New equipment with easy-to-use controls and automation lowers the learning curve needed for new operators and keeps productivity levels up. This shows that automation can help the construction industry challenges of the industries shortage of skilled labor. Rising costs for materials and equipment maintenance require companies to find cost effective solutions. Using high quality aftermarket parts for compact construction equipment, keeps your machines durable and efficient while keeping operation costs under control and minimizing downtime. Conclusion Investing in the right construction equipment is essential for building the roads and bridges we depend on. The need for new and improved infrastructures keeps increasing, and we must ensure they are efficient and sustainable. By choosing innovative solutions and high-quality machinery, we can make a lasting difference and help our communities thrive.

The construction of a bridge that will allow high speed trains to pass under the busy A43 near Brackley has taken a major step forward with the structure’s enormous steel beams lifted into position during a series of three weekend closures. The A43 – which links Oxford, Brackley and Northampton – is a vital route, providing access to Silverstone and connections between the M40 and M1. It was reopened just before midnight on Saturday night after the last of three weekend road closures. Preparation for the work began in 2023 when HS2 engineers, working closely with National Highways, realigned the road to create an ‘island’ between the two carriageways big enough for the construction of the new bridge deck. Using a ‘top-down’ approach, they sank 52m deep piled foundations and then built the pile caps and piers that will support the 66-metre-long bridge deck carrying the road. This weekend, they lifted the last parts of the seven steel beams that will support the bridge deck using a 750-tonne crane. With the beams now in position, the team will focus on the concrete deck and parapets. Once the bridge has been built, the road will be moved back onto the new bridge and excavation can begin to create space for the railway to pass underneath. This multi-stage approach was designed to keep traffic flowing and disruption to a minimum. HS2 Ltd’s Senior Project Manager Elizabeth Longinotti said: “The A43 is a busy route between Brackley and Northampton and I’d like to thank drivers for their patience over the last three weekends, allowing us to safely lift the enormous steel beams into position while the road was closed. “With the beams now in place, we can focus on the next part of this complex multi-stage project – pouring the concrete deck ready for the road to be moved onto the new bridge early next year.” National Highways Route Manager, Bill Freeman, said: “This is an enormous project which will inevitably impact on people using our roads but we have worked very hard for a long time now to keep that disruption to a minimum. “For a number of years we have been liaising with HS2 and their partners to develop a plan which would reduce the disturbance to road users during the construction of this huge structure. “We have also taken advantage of the road closures to expedite our own works improving drainage and repairing the slope along the A43, between Brackley and Syresham, reducing the need for further disruption.” The 80km stretch of railway that passes Brackley – including the A43 bridge – is being delivered by HS2’s main works contractor EKFB, a team made up of Eiffage, Kier, Ferrovial Construction and BAM Nuttall working with ASC (a joint venture between Arcadis, Setec and COWI). They worked with National Highways and EKFS’s sub-contractor, Kier Transportation, to construct the temporary realignment, to keep traffic flowing during the work. EKFB Deputy Project Director Timothée Scherer, said: “The successful execution of the beam lift represents a crucial milestone in our project. This accomplishment underscores the diligent efforts and unwavering commitment of our team, who have meticulously worked to ensure the safe and efficient installation of the beams. This progress brings us significantly closer to the realisation of this essential infrastructure project, which is destined to substantially enhance regional connectivity and transportation”. Tim Boardman, Senior Project Manager at Kier Transportation, added: “It’s fantastic to see the beam lift take effect, and we’re now starting to see the bridge really take shape. Putting this solution into place has required a huge amount of expertise and collaboration with our partners, and we’re proud of the impact it will have. We look forward to moving onto the next stages of the project, while continuing to work hard to minimise disruption for road users and the local community.” The last few weeks have also seen significant progress for the nearby Turweston viaduct near Brackley, with the 80m long deck beam now slid fully into position. The 591-tonne steel structure was assembled to one side and slid out on special pads covered in PTFE – a Teflon-like material usually found on the surface of a non-stick frying pan – used to minimise friction between the deck and the temporary steel bearings on top of each of the piers. Turweston is one of five viaducts on the project which use an innovative ‘double composite’ structure, with layers of reinforced concrete on the top and bottom to create a much more structurally efficient box-like span which dramatically cuts the amount of embedded carbon in the design. In total there are more than 500 bridging structures on the HS2 project – which is designed to improve connections between London, Birmingham and the North while freeing up space for more local trains on the most congested southern end of the existing West Coast Main Line into London Euston. These range from small footbridges and underpasses, to innovative ‘green bridges’ designed to help wildlife cross the railway, massive motorway bridges and the record-breaking Colne Valley viaduct. The last few months has also seen significant progress at HS2’s other major viaducts, with the first completed viaduct deck at the complex Delta Junction outside Birmingham and the Small Dean and Wendover Dean deck slides in Buckinghamshire. Building, Design & Construction Magazine | The Choice of Industry Professionals