Engineers this week began a delicate job that will see almost half a kilometre of bridge deck slid into position over the next year, high above the Misbourne Valley in Buckinghamshire, as HS2’s innovative Wendover Dean Viaduct enters a critical new stage of construction. The 450m-long viaduct will be the first major railway bridge in the UK to be built with a ‘double composite’ approach, which uses significantly less carbon-intensive concrete and steel than a more traditional design – and has allowed HS2 to halve the amount of embedded carbon in the structure. It is one of 50 major viaducts on the HS2 project – which is designed to improve connections between London, Birmingham and the North while freeing up space on the most congested southern end of the existing West Coast Main Line. Instead of using solid pre-stressed concrete beams to form the spans between the viaduct piers, the ‘double composite’ structure uses two steel beams sandwiched between two layers of reinforced concrete to create a lightweight and super strong hollow span.  Due to the length of the viaduct, the deck is being assembled in three stages, ranging from 90m to 180m sections, with each one pushed out from the north abutment before the next section is attached behind it. This painstaking process means that the weight of the deck will increase with each push, up from an initial 590 tonnes this week to 3700 tonnes by the end of the year. Tomas Garcia, HS2 Ltd’s Head of Civil Structures said: “Double composite structures maximise the combined strength of steel in tension and concrete in compression. This approach has been tried and tested around the world and it’s great to see it applied on this scale for the first time in the UK at Wendover Dean. “Once complete, HS2 will help enhance the existing rail network by freeing up capacity on the busy West Coast Main Line and almost halving journey times between London and Birmingham. This viaduct will play a crucial role enabling those faster and more reliable services – and I hope it will also inspire other projects around the UK to consider this innovative approach to construction.” The viaduct is being built by HS2 Ltd’s main works contractor, EKFB – a team made up of Eiffage, Kier, Ferrovial Construction and BAM Nuttall – with the manufacture and installation of the beams being led by specialists at Eiffage Metal. A winch is used to push the deck forward at a speed of around 9 metres per hour, sliding across Teflon pads to reduce friction – a material usually found to the surface of a non-stick frying pan. It is the longest deck slide on the HS2 project to date. At this point in the Chilterns the railway will be on a slight gradient, so to help maintain control, the deck – which will eventually weigh the same as 264 double-decker buses – is being pushed slightly uphill, with the finish point approximately 1.8m higher than start point. James Collings, EKFB’s senior engineer, said: “The project team has reached a fundamental milestone in the build of this industry-leading viaduct. We’re progressing well with the first-of-three steel launches being conducted this year and already looking forward to seeing this viaduct come to life. Along with our supply chain partners, Eiffage Metal, we’re proud to be delivering this viaduct safely and to programme.” EKFB worked with their design partner, ASC (a joint venture between Arcadis, Setec and COWI) and architects Moxon on the ‘double composite’ approach which was inspired by structures on the French high speed TGV network. The approach is set to cut the carbon footprint of the structure by 56% – saving almost 13,000 tonnes of embodied carbon – and helping HS2 achieve its goal of halving the amount of embedded carbon in construction. The beams are made of ‘weathering steel’ which naturally fades to a dark brown colour over time and will help match the natural tone of the surrounding countryside. A similar approach – using weathering steel and a double composite structure – is also being taken at the nearby Small Dean Viaduct which is currently at a much earlier stage of construction. Weathering steel gets its characteristic colour from a surface layer of corrosion which protects the steel and removes the need for regular painting. The Wendover Dean Viaduct will be supported by nine evenly spaced piers, some of which will be up to 14 metres high. These consist of a series of hollow pre-cast concrete shells – manufactured in Northern Ireland – which are placed on top of each other and filled with concrete and steel reinforcing. This approach was chosen to enable a crisp, clean external finish to the concrete, cut the amount of work on site and reduce disruption for local residents. The last few months has also seen significant progress at HS2’s other major viaducts, with the first concrete poured for the approach viaducts for Birmingham Curzon Street station, the first beams installed at Thame Valley near Aylesbury and the Delta Junction in North Warwickshire. In total, HS2 is building more than 500 bridging structures – ranging from small road bridges to massive viaducts like record-breaking Colne Valley Viaduct which will become the longest in the UK. Building, Design & Construction Magazine | The Choice of Industry Professionals

The start of 2024 sees the emergence of a new brand in the UK highway sector, as Core Highways Group announces it is rebranding as Core Highways, bringing all its subsidiaries together under one brand and revealing a brand-new logo, website, colours and updated values.    This strategic milestone sees the trusted and respected brands of Amberon, Barrier Services, Forest Traffic, JTM Signs and MLP Traffic come together as one.  With over 1,300 staff and more than 1,000 directly employed operatives working in a combined turnover business of £120m pa, Core Highways automatically becomes one of the largest temporary traffic management and barrier companies in the UK, with almost 40 depots across England and Wales, with further natural growth and expansion planned. Lizi Stewart, CEO of Core Highways, explained “Becoming Core Highways means that we can combine our knowledge and expertise for our customers across England and Wales, giving them access to more skills and expertise in temporary traffic management, barrier solutions and events signage.  Our dedicated and knowledgeable team have hundreds of years of experience in providing solutions for customers across England and Wales’ road networks at high and low speed.  As a team we are stronger together, supporting one another and our customers to deliver.  Becoming one will give our customers quicker access us to our deep well of technical excellence as well as our innovation and best practice, such as our Decarbonisation Project Roadmap and our award-winning Digital Care Initiative. She continued “Our business is our people, and by better connecting our passionate, skilled and customer focussed team under the Core Highways brand, we are better able to support our customers and their stakeholders.” Core Highways is a leading provider of temporary traffic management, barrier solutions and events signage with the ability and expertise to deliver across the UK, offering local knowledge on a national scale, from small schemes to major projects. For more information on Core Highways, please visit www.corehighways.com Building, Design & Construction Magazine | The Choice of Industry Professionals

Plans for a new £25 million rail station in West Yorkshire are making significant progress, with completion expected by late 2026. Survey work is currently underway to finalise detailed designs for the long-awaited Elland Rail Station. Contractor Keltbray Infrastructure Services Limited is aiming to complete the final stages of development work by summer 2024. Following this, the West Yorkshire Combined Authority will review a full business case for the station, moving the project closer to construction. The initiative is a collaboration between the West Yorkshire Combined Authority and Calderdale Council. The council is nearing completion of designs for ambitious access routes, which include two new pedestrian and cycling bridges. A key milestone was recently achieved with the council’s approval of a planning application for the station’s access infrastructure. Tenders for the final design phase of the access package were submitted last month, and the council is now in the process of selecting a contractor. The new station, set to be a valuable addition to the Calder Valley line, will strengthen Elland’s transport links to key regional hubs, including Leeds, Huddersfield, Bradford, and Manchester. This transformative project is expected to deliver improved connectivity for the town, fostering economic growth and offering enhanced travel options for residents and visitors alike. Building, Design & Construction Magazine | The Choice of Industry Professionals

Costain, the infrastructure solutions company, has successfully completed works to ensure today’s entry into service of the upgraded Gatwick Airport station. The four-and-a-half-year construction and refurbishment project began in June 2019 and significantly upgrades the station’s ability to handle growing passenger numbers. Costain first delivered the planning and design stages and was then appointed to deliver the improvement works. The project has created a safer, more convenient interchange between the station platforms and Gatwick International Airport.  The brief included the construction of a new concourse and staff accommodation, as well as carrying out the reconfiguration of railway infrastructure. Costain has also refurbished the existing station concourse and footbridges, enhancing the one-way system between the airport and the station.  There are new customer information systems, more ticket gates and significant improvements to accessibility with the installation of eight new escalators and five new lifts. Costain’s project director, Andy Hudspith, said: “We’re really proud of the work we’ve undertaken for Network Rail to upgrade the station at Gatwick Airport.  The project has been complex and challenging, but we’re pleased that our work will enhance the passenger experience and improve journey times for everyone who uses and passes through the airport. The biggest challenge was to achieve the transformation without negatively impacting rail or airport operations, and with minimal impact on passengers, all while working above a live railway line and within the heart of the world’s busiest single runway airport. We’re delighted to have delivered such an important project successfully.” Gatwick airport is the UK’s second busiest airport and its station is one of the ten busiest stations in the UK outside of London, handling more than 20 million passengers a year. The redevelopment works were designed to provide crucial increased capacity to support airport growth and significantly enhance the passenger experience. The new second concourse has been built above the existing platforms five, six and seven, doubling the space available for passengers at the station.  The new exit concourse measures 1727 square metres, the size of eight tennis courts and provides a spectacular new entrance space to the airport.  The roof of the new concourse is formed using four clear spanning steel trusses that connect the platform and concourse environments in a sweeping arch form. The trusses are finished in gold anodised aluminium cladding, bringing warmth and prestige to the space. In between the trusses there are 945 square metres of ETFE pillows (a lightweight alternative to glazing) which floods the concourse with natural light, using the same technology as the biospheres at the Eden Project in Cornwall. Accessibility has been improved throughout, for example wheelchairs users’ access has been improved through the widening of the historically narrow platforms five and six. New tactile signage, including braille, has been integrated into the wayfinding signage strategy and there are 70 new hearing loops at key points.  A 24/7 special assistance point has been created in the existing station concourse to provide additional support for passengers with reduced mobility and disabilities. As well as encouraging sustainable travel, Costain also targeted reducing carbon emissions during the building and operation of the new concourse.  The project used almost 3,000m3 of low-carbon concrete, saving 517 tonnes of CO2 emissions and £12,500 in costs. LED lighting was used throughout the station, escalators were fitted with reduced speed technology to lower emissions when not in use, and high efficiency gearless lifts were installed as well as a hybrid heating and cooling system. An estimated annual cost saving of nearly £60,000 and an annual reduction of 144 tonnes of carbon emissions are expected from these features. David Taylor, Costain’s interim managing director for Transportation, commented: “The development at Gatwick transforms the existing station and provides a greatly enhanced experience for passengers. Costain’s extensive capability to deliver complex programmes has been showcased with this project; we’ve used leading edge smart technology and worked sustainably to create a wonderful new space for passengers. It’s been a particularly collaborative project which has helped enormously with its success; from an engaged and supportive supply chain to Network Rail’s invaluable assistance with possessions of the railway.” Building, Design & Construction Magazine | The Choice of Industry Professionals