The Mersey Gateway Project

Bridge building machine ‘Trinity’ starts work with first concrete pour for Mersey Gateway approach viaduct deck

January 21, 2016MerseylinkNews

Merseylink’s 1,700 tonne bridge-building machine, which looks and operates a bit like a giant Meccano set, has started work on England’s biggest new bridge.


The machine, named Trinity, is a Movable Scaffolding System (MSS), specially designed and built to construct the curved viaducts leading to the Mersey Gateway Bridge, the centerpiece of the Mersey Gateway Project.

Trinity began work today in Widnes with a concrete pour for the first deck section of the northern approach viaduct, which will lead to the new bridge.

Around 160 truck loads of concrete are being poured into the 1,170 cubic metre mould over a period of around 24 hours.

Trinity is 157m long, 22m wide and weighs 1,700 tonnes. She will be on site for the next 14 months.

She will act as a giant concrete mould, known as ‘formwork’, for the central deck of the north and south elevated approach viaducts, which will be constructed in sections or ‘spans’ approximately 70m in length. It will take a few weeks to build each of the 19 spans, with this element of work due for completion in March 2017.

The process involves locking Trinity onto the bridge piers and then pouring concrete into the mould to create a deck span. Once the first span is complete, the equipment will then move along via hydraulic jacks to create the next deck span, and the process begins again.

Hugh O’Connor, General Manager for Merseylink, said: “This is a hugely exciting time for our construction teams. An enormous amount of effort has gone into preparing and testing Trinity ahead of today’s concrete pour. We are delighted to achieve this important milestone and get this next phase of the project underway.”

Cllr Rob Polhill, Leader of Halton Borough Council and Chair of the Mersey Gateway Crossings Board, said: “This is a significant step in the project, as the MSS has generated extensive interest both locally and globally. People

will be able to see Trinity in action online via the webcam and by keeping a close eye on the Mersey Gateway social media channels.”

Trinity is unique to the Mersey Gateway Project and is being operated by MSS specialists ConstruGomes, working alongside Merseylink engineers.

Once Trinity has constructed the central part of the deck, a machine called a wing traveller will then be used to build the outer part of the north approach viaduct. The wing traveller is currently being assembled on site.

See how the MSS operates to build the deck of the approach viaducts:

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