Construction teams have cast the second span of the Mersey Gateway’s south elevated approach viaduct 25m high above the Manchester ship canal.
The Mersey Gateway’s giant bridge-building machine, named “Webster”, built the section of the approach road in Runcorn that will take traffic across the canal and onto the new bridge.
The work involved pouring around 160 truckloads of concrete into the 1,155m3 mould over a 24-hour period.
In total, the movable scaffolding system (MSS) will cast eight reinforced concrete spans to create the central section of the approach road.
“This was one of the more challenging pours on the project as working above the ship canal required extra planning and a change in logistics. We couldn’t place the concrete pumps underneath the machine or they’d have been under water. Instead we used additional pumps on top to give us access to the concrete,” said Merseylink operations manager for the approach viaducts Marc Heaps.
The 1,700t Webster is 157m long, 8m high and 22m at its widest point. It was named by Halton schoolchildren after local engineer John James Webster who built the Widnes Transporter Bridge.
The machine is accompanied on site by a wing traveller machine, which will build the outer lanes of the approach road to create the full six-lane width. The 280t machine was recently lifted into place using the UK’s largest crane boom.
When complete, the south approach viaduct will link the main road network in Runcorn to the new Mersey Gateway bridge, improving connections locally and across the wider region.