HS2 yesterday revealed new timelapse footage showing the latest stage of a complex year-long project to slide almost half a kilometre of bridge deck into position, high above Buckinghamshire’s Misbourne Valley. Over a 20 hour period last week, engineers working for the high-speed rail project carefully slid the 3130-tonne structure 270 metres, using Teflon pads to reduce friction – a material usually found to the surface of a non-stick frying pan. The deck of the Wendover Dean Viaduct – which will eventually stretch for 450m – 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 at the start of work in January – to 3700 tonnes by the end of the year. 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. 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. HS2 Ltd Senior Project Manager Ben Sebastian-Green said: “It’s great to see so much progress at Wendover Dean Viaduct over the last few days – with all the piers and the first three slides now done. The narrow site has always made it a challenging place to build, but I’m really impressed by how everyone’s pulled together to get us where we are today. “Once complete, the viaduct will form a crucial part of the HS2 project – carrying fast trains between London and Birmingham and freeing up space on the existing mainline for more local and freight services.” The Wendover Dean Viaduct is the first major railway bridge in the UK to be built with a ‘double composite’ structure, which uses significantly less carbon-intensive concrete and steel than a more traditional design. Instead of using solid pre-stressed concrete beams to form the spans between the viaduct piers, the hollow ‘double composite’ structure uses two steel beams sandwiched between two layers of reinforced concrete to create a more efficient super strong span.  A similar approach will also be used for HS2’s Small Dean, Westbury, Lower Thorpe and Turweston viaducts. All five viaducts are 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. James Collings, EKFB Agent said: “It’s great to see the next phase of the installation of the steel work. The team have worked together to achieve the delivery and welding of the structure and installation of the precast concrete planks as well as completion of the nine piers. I am extremely proud of the team” 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 and other European high-speed networks. The approach is set to cut the carbon footprint of the structure by around half and help 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. 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 are up to 14 metres high and all of which are now complete. These were formed from a series of hollow pre-cast concrete shells – manufactured in Northern Ireland – which were 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 sections of the approach viaducts for Birmingham Curzon Street station completed and the first beams installed at 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 first opening road bridge across the River Clyde is a step closer to completion as the first section of the Renfrew Bridge has arrived in Renfrewshire. Working on behalf of Renfrewshire Council, the £117 million Clyde Waterfront and Renfrew Riverside project will see the new bridge connect Renfrew with Yoker and Clydebank and open up work, health, education, and leisure opportunities on both sides of the Clyde – bringing thousands of additional jobs, investment, and developments to the riverside. The south section of the 184-metre cable-stayed twin-leaf bridge has arrived on the River Clyde after travelling for seven days on a barge across the North Sea, English Channel and Irish sea having been fabricated in the Netherlands. The team will install the first section on the Renfrew side of the river at Meadowside Street, ahead of the north section of the bridge arriving next month, where it will be fixed into place at Dock Street in Yoker. Jim Armour, GRAHAM Contracts Manager said: “The arrival of the first section of the bridge marks a significant milestone on the project- a fantastic achievement by the team. Over the next few weeks, the team will be working hard to prepare for the north section of the bridge to arrive, where it will be fixed into place. The new bridge is a vital piece of infrastructure that demonstrates civil engineering excellence, driving economic growth on either side of the Clyde”. Renfrewshire Council Leader Iain Nicolson said: “It’s fantastic to see the first section of the bridge arrive in Renfrew and the project take a significant step forward as this is going to be transformational for the local area, wider Renfrewshire, and the City Region.  “The opportunities that the new bridge, and its new connecting roads and active travel routes, will offer communities and businesses are exponential and the project as a whole will provide a substantial boost to the economy and attract more jobs to the area – in addition to more than 950 already created during the construction phase.  “With this project linking into the Advanced Manufacturing Innovation District Scotland (AMIDS) at Netherton next to Glasgow Airport, it is an exciting time for Renfrewshire and outlines the council’s continued ability to deliver nationally significant infrastructure projects successfully.” In addition to the new bridge, the project will create additional connecting roads, cycling and walking routes which will link Inchinnan Road in Renfrew with Yoker Railway Station, using the new Renfrew North Development Road. It will also see improved access for businesses and suppliers to Scotland’s home of manufacturing innovation AMIDS, which is being developed by the Council in collaboration with Scottish Government and Scottish Enterprise. For more information on the project, visit www.renfrewshire.gov.uk/citydeal Building, Design & Construction Magazine | The Choice of Industry Professionals

HS2 has released timelapse and drone footage showing contractors moving a 1,100 tonne composite viaduct into place over two M42/M6 link roads in North Warwickshire. The 158-metre-long structure was moved into place in 13 hours using a specialist push-pull jacking technique. The ‘East M42-M6 Link Viaduct’ is one of 13 viaducts which make up HS2’s triangular Delta Junction. This section of the railway enables high speed trains to travel between London, Interchange Station in Solihull and Birmingham Curzon Street Station. The operation was completed 10 hours ahead of schedule during a weekend road closure, enabling the motorway link roads to be opened earlier than planned. It was delivered by a team of 25 people from specialist steelwork company Victor Buyck Steel Construction (VBSC), working on behalf of HS2’s main works contractor Balfour Beatty VINCI (BBV). HS2 Ltd, BBV and National Highways collaborated to minimise disruption for people using the roads and enabling this engineering feat to take place. This was the second ‘launch’ of this structure to move it into its final position over both westbound and eastbound motorway link roads. In February, the first launch took the first 84 metre section of the viaduct to its halfway position over the westbound link road. Since then, three further steel girders were welded to the back of the first section and 38 precast concrete slabs were installed to complete the 158-metre-long structure. By installing the slabs prior to launch, the number of highway closures required to finish the composite deck has been significantly reduced helping to keep future closures of the link road to a minimum. Over the summer, a similar two-stage operation will move the identical ‘West M42-M6 Link Viaduct’ which runs parallel to the East Link Viaduct. Building, Design & Construction Magazine | The Choice of Industry Professionals

HS2 has begun foundation works for a key bridge that will take a major A road over the new high-speed railway just outside Brackley, after successfully completing the temporarily realignment of both carriageways. The A43 – which links Oxford, Brackley and Northampton – is a vital route, providing access to Silverstone and connections between the M40 and M1. Just two weekend closures were needed during the seven-month realignment project, with HS2 working closely with National Highways to create an ‘island’ between the two carriageways big enough for the construction of the new bridge deck. HS2 engineers have now begun work on the 52m deep piled foundation that will support the weight of the bridge. These will be topped with concrete pile caps and piers supporting the 66-metre-long bridge deck that will carry the road. Once the deck has been completed, the road will be moved back over 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 reduce disruption. HS2’s Senior Project Manager Elizabeth Longinotti said: “It’s great to see the start of foundation works for the A43 overbridge. Once complete, HS2 will boost connections between Britain’s two largest cities while freeing up space for more local services on the existing network. But it’s also vital that we keep the local routes which people depend on open while we build the railway. “That’s why we’ve worked closely with National Highway and our contractors to design and deliver a complex multi-stage project which will keep disruption to a minimum while we deliver this key overbridge.” The almost 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 Highways, to construct the temporary realignment over a seven-month period last year. National Highways Network Planner for the East Midlands, Phil Shaw, said:  “We always strive to minimise disruption for people using our roads when any work is being carried out and have liaised closely with our HS2 partners to do so on this complex project. “Working together we have not only been able to limit the impact on drivers of building the overbridge but have also been able to take advantage of any road closures to carry out some routine maintenance work which means we won’t have to come back and close the road another time.” EKFB’s Project Director, Tony Wehby, said: “EKFB’s priority was to minimise disruption for local road users and to keep communities connected as best as possible. The road closures were minimised to short periods and often overnight.  “The team is thrilled to be at this point in the construction programme and the start of piling works signifies outstanding team collaboration to get it to this stage. This a complex set of works and is a unique construction project in itself, that heavily leans on the expertise of the multiple contractors involved in delivering these works to a high and safe standard.” The A43 is one of around 500 bridges 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 deck slide for the enormous Delta Junction over the A42/M6 link road outside Birmingham and the start of a half-kilometre deck slide at Wendover Dean. Route wide, HS2 is now at peak construction, with 28,000 people employed directly and across the UK-wide supply chain. Building, Design & Construction Magazine | The Choice of Industry Professionals

The final two major structures being built to bring HS2 into Birmingham have been approved by local councils – marking another significant milestone for the project. Approval has been granted for the design of two new viaducts, meaning eight “Key Design Elements” (KDEs) on the West Midlands section of the route have now passed the Schedule 17 process. KDEs are structures on the HS2 project identified as being significant because of their size, proximity to communities, or location within sensitive areas. Because of these challenges, HS2 has undertaken extensive engagement with local communities to listen to people’s views and incorporate feedback in the design of the structures where possible. The River Blythe Viaduct has received Schedule 17 planning approval from Solihull Metropolitan Borough Council. A 475-metre low-lying structure, just south of the new HS2 Interchange Station in Solihull, it is designed to skim the flat, agricultural landscape as it crosses the River Blythe, the floodplain and Meriden Road near Hampton in Arden. Feedback from the local community has been incorporated into the planning of the construction of this viaduct, particularly regarding tree planting and protecting the local environment in the areas near the river which are designated as a Site of Special Scientific Interest. Saltley Viaduct has received planning approval from Birmingham City Council. It is a 225-metre structure, including approaches, located two miles north-east of Birmingham city centre, and will take the B4144 road over the HS2 line, the Birmingham and Warwick Junction Canal, the Birmingham and Derby rail line and the River Rea. It will be an important crossing point, providing access to the city centre and the wards of Nechells and Alum Rock. A wider pathway to make room for cyclists, additional lighting, and replacing stainless steel material with weathering steel panels and a perforated pattern, were key requirements from local people, which have all been incorporated. Stephen Powell, HS2 Ltd’s Head of Delivery said: “Achieving these two KDE planning approvals is a significant milestone for the project. It’s been hugely important for us to engage and consult with communities as we reach the final design stages of these key structures in the West Midlands, and we’re very grateful for the feedback they have provided. “Our designers have incorporated local feedback in all of these Key Design Element structures, including enhanced environmental features, use of materials and additional amenities such as footpaths and cycling tracks in the areas around them, ensuring that we have the best outcome for everyone.” Nick McGough, Director at Weston Williamson + Partners, and Lead Architect for the Balfour Beatty VINCI Design Joint Venture, which is designing HS2 in the West Midlands, said: “All of HS2 needs to be designed sensitively but KDE structures in particular were identified through the parliamentary process due to their scale and significance. The whole team has worked incredibly hard for over 6 years to engage local communities in a process which has involved Local Authorities, key stakeholders and the HS2 Independent Design Panel. “The approvals received for the River Blythe Viaduct and Saltley Viaduct complete the set of KDEs in the West Midlands which will bring HS2 into central Birmingham, whilst contributing positively to local communities. For the River Blythe Viaduct this includes landscape enhancements whilst at Saltley, active travel is encouraged with dedicated pedestrian and cycleways separated from road traffic.” One other KDE in Birmingham is: One other KDE in Solihull is: Four other KDEs in North Warwickshire are: These KDE structures form part of the section being designed and built by Balfour Beatty VINCI, HS2’s construction partner in the Midlands, together with a Design Joint Venture of Mott MacDonald and SYSTRA with Weston Williamson + Partners as architects. This project team is responsible for delivering the 90km stretch of the route spanning from Long Itchington in Warwickshire to the centre of Birmingham and on to Handsacre in Staffordshire. A workforce of over 9,000 people and 400 companies in the West Midlands are helping to build HS2. In total BBV are building 42 viaducts (totalling 11km), 62 overbridges, 62 embankments, 34 cuttings, 28 underbridges, 11 underpasses, along with two twin bore tunnels and two cut and cover tunnels (totalling 15km). Building, Design & Construction Magazine | The Choice of Industry Professionals