HS2 has completed its first major piece of infrastructure with the installation of a large bridge over the M42 in the West Midlands.
Work to install a 65-metre bridge, weighing 2,750 tonnes and spanning the width of the M42, was completed in just two days and ahead of schedule as the motorway reopened 22 hours earlier than planned. The works, near the site of HS2’s future Birmingham Interchange station, are the first visible sign of the arrival of HS2, Britain’s future high-speed railway.
Working with HS2 enabling works contractor, LMJV (Laing O’Rourke and J. Murphy & Sons Joint Venture), the bridge was assembled to one side of the M42 motorway by Laing O’Rourke subsidiary Expanded Structures and specialist bridge builder Cleveland Bridge.
Although the motorway is 47.5 metres at this point, the bridge crosses at an angle, so the bridge had to be 65 metres long and was constructed from 1,130 tonnes of steel plate girders and 1,610 tonnes of precast and in-situ concrete.
Meanwhile, the bridge abutments were constructed using 62 piles, each 32 metres long and weighing nearly five and a half tonnes, as well as 115 concrete abutment shells made by Explore Manufacturing, another Laing O’Rourke company, at its factory in Worksop, Nottinghamshire.
The M42 was closed between junctions 6 and 7A (northbound) and junctions 7 and 6 (southbound) at 21:00 on Friday 7 August 2020. Two self-propelled modular transporters (SPMT), provided by Dutch lifting specialist Mammoet, moved the bridge from its assembly area and then along the motorway to its prepared home.
Each SPMT had 28 axles and their combined capacity was 4,032 tonnes. The 2,750-tonne bridge, along with its cradle of 330 tonnes of supporting steelwork, was thus well within the lifting capability of the two transporters.
The 448-wheel transporters took just one hour and 45 minutes to move the bridge span 150 metres, where it was affixed to a composite concrete deck to complete the overall bridge structure.
HS2 CEO Mark Thurston was there to see it, accompanied by West Midlands Mayor Andy Street. “This new road bridge is the first permanent structure to be installed along the route of Britain’s new railway,” Mark commented.
“Today represents an important milestone for the project and the West Midlands region – which is already benefiting from thousands of jobs and renewed investment as a result of HS2.
“Constructing the bridge off site, and using innovative engineering practices to install it over the motorway, enabled us to carry out the work in just two days, keeping disruption to a minimum for road users.”
This is the first of four bridges to be built close to the new Birmingham Interchange station, using an innovative modular design that will reduce the time required on site and keep road closures to a minimum. A road bridge, not a railway bridge, it will form part of the regional road network, which is being remodelled to improve the circulation of traffic around the HS2 railway line and connect the existing road network to the new station.
Having watched the installation, Mayor Andy Street said: “Seeing major construction activity like this in Solihull is hugely encouraging as it shows HS2 is now truly underway. In just a few years, the HS2 station at Interchange and further investments in public transport will help make Solihull one of the best-connected places in the UK.
“Today’s work also comes at a critical time for the West Midlands, as we look to bounce back economically from the coronavirus crisis. Major infrastructure projects like HS2 have a critical role to play as they help stimulate demand and create and secure local jobs for local people.”
HS2’s new Birmingham Interchange station will be at the heart of the UK Central Hub growth area, which will create 70,000 new and safeguarded jobs, up to 5,000 new homes and 650,000 square metres of commercial space.
Andrew Stephenson MP, Minister of State at the Department for Transport who has responsibility for HS2, along with Northern Powerhouse Rail and the Transpennine route upgrade, said: “The installation of this innovative bridge across the M42, ahead of schedule and with minimum disruption, demonstrates our dedication to delivering this vital rail connection to the West Midlands as efficiently and as quickly as possible.
“It’s an achievement of British construction and marks another step forward in this historic project, which will leave a legacy of better connections and regional growth for generations to come.”
Companies from the Midlands and the North played a leading role in the construction of the deck components and supply of the 1,130 tonnes of steel plate girders and 1,610 tonnes of precast and insitu concrete.
LMJV project director Simon Russell said: “This is British construction, design and engineering innovation at its finest.
“Major components of the bridge and its supports were built offsite under safe, high-quality conditions, then transported to site for assembly. Advanced digital capabilities allowed us to design all elements of the structure in a virtual world, before building it for real, and I am delighted that the work was completed safely and ahead of schedule.”
Further work in preparation for the arrival of HS2 is scheduled to take place later this year. A similar bridge will be installed over the A446, ahead of two more bridge structures that will span the route of the new high-speed railway line.