There are 155 beams supporting the reinforced concrete road deck of the viaduct, which connects the new bridge to the Central Expressway in Runcorn.
Astmoor Bridgewater Viaduct is part of the new 9.2km link road, diverting the majority of traffic across the new Mersey Gateway Bridge to relieve congestion on the Silver Jubilee Bridge in Runcorn.
Each beam on the Astmoor Bridgewater Viaduct is approximately 40 metres long and weighs up to 110 tonnes. They have been installed by a 650-tonne capacity crawler crane.
Halton Borough Council is the client for the project and it awarded a 30-year contract to design, build, finance and operate the project to the Merseylink Consortium in 2014. Equity partners are Macquarie Capital Group, BBGI, and FCC Construcción. The construction joint venture is made up of Kier, Samsung C&T and FCC.
Merseylink general manager Hugh O’Connor said the installation marked another major milestone for the project. “As we draw closer to completion we’re passing more and more of these vitally important landmarks. Earlier this month we completed 50% of the main bridge deck, and this week we’re celebrating completing the final beam installation,” he said.
“The skill it takes to position these huge pieces of reinforced concrete into place is immense and I would like to thank all of the construction crews and crane operators who have helped us reach this milestone.”
Huge beams have also been installed for road elevations at the Ditton, Widnes Loops and Lodge Lane junctions on the project.
Merseylink project director Gareth Stuart said: "Improvements to local highways are a key feature of this project. Completing this stage of the project is a huge achievement and brings us closer to finishing.
“When complete, the new link road will provide a seamless route across the new bridge making it quicker and easier for people to travel between Runcorn, Widnes and beyond."
Councillor Rob Polhill, leader of Halton Borough Council, said: "This is a hugely exciting moment for the project. The bridge deck is over halfway finished, and the completion of the final beam installation means the new road network is taking shape.”