The first of 146 stay cables connecting the south pylon to the main bridge deck has been installed at the £500m Mersey Gateway second river crossing.
Construction teams put the 52-metre long cable in place at the pylon in the Mersey estuary yesterday, part of the cable system to support Halton’s new 1,000-metre long reinforced concrete bridge.
Form traveller machines are casting the deck segments from each side of the three pylons and once the concrete has reached the required strength the stay cables will be installed along the bridge.
Each stay cable consists of up to 91 individual steel strands that sit inside a stay pipe, the outer casing that provides protection from weather-related corrosion.
More than 810 miles of the strands will be used on the project, around the same distance from John O’Groats to Land’s End.
Gareth Stuart, project director of the Merseylink construction joint venture, said: “This marks a momentous occasion for the project. The stay cables will be an iconic feature of this landmark structure making it one of the most recognisable bridges in the UK. We’re now entering a new, very visual phase of the bridge construction, where people will be able to see the stay cables connected to the bridge deck as it emerges across the river week by week.”
Together the 146 stay cables have a total load bearing capacity of about 53,500 tonnes, which is heavier than the QE2 ocean liner.
The stay cables all vary in length; the shortest is 41 metres and the longest measures around 226 metres.
The iconic design of the Mersey Gateway bridge is based on a cable-stayed structure with three pylons.
Stay cable strands and anchor samples are on display at the Mersey Gateway visitor centre located at the Catalyst Science Discovery Centre in Widnes.