The bridge’s central deck is now complete but still free standing and this 644 metre cantilever itself won’t last long. Soon, it will be connected to the flanking towers and viaducts to form the final superstructure.
However, experts at Guinness World Records have inspected and officially ratified the record while the deck is in this world-record breaking but still temporary state.
Since last September each 16 metre, 750 tonne section of deck has been added piece by piece and the central tower deck fan is now fully complete.
Each deck section is added ensuring that the cantilever remains balanced, which avoids placing too much stress on the concrete tower by adding deck segments sequentially at alternate ends. Using this method means that there can be up to 4 metres displacement in the deck itself, in the period between one deck lift and the next. While this is entirely normal and expected, it has led members of the public to ask if the deck fans will actually meet.
Until now the balanced cantilever method has never been used to construct a bridge this big.
Cabinet Secretary for the Economy Keith Brown said:
“We can all agree the Queensferry Crossing is a modern marvel and a world-class feat of engineering. It’s only fitting then that the bridge has been awarded a Guinness World Records title.
“This world-record breaking structure is all the more remarkable when you consider the extreme weather conditions often experienced out in the Firth of Forth, especially working up above the water between 60 metres and 210 metres high. Everyone who has worked so hard and skilfully to build this amazing bridge is a world record beater in their own right.
“It won’t be long before the balanced cantilever disappears, when the small gaps between the towers are closed. But the record is still there to be beaten and the Queensferry Crossing will still be the tallest bridge in the UK and longest bridge of its type anywhere in the world.”
Alan Platt, FCBC Construction Director said:
“Construction work is going well on all three towers. This unique achievement at the Centre Tower is a feat of engineering which the whole FCBC team is immensely proud of. This is leading edge civil engineering and I’m delighted to pay tribute to the skills and dedication of everyone involved.”
Iain Cookson, FCBC Manager Centre Tower said:
“It’s not every day you get to achieve a Guinness World Records title. The construction of this record-breaking cantilevered structure has involved the installation of 36 separate steel and concrete composite deck sections.
These massive sections measure approximately 40 metres wide, 16 metres long are 5 metres deep and weigh an average of 750 tonnes. Each one had to be lifted up 60 metres above sea-level before being welded and bolted into position. Simultaneously, we had to create and install the steel stay- cables which will bear the weight of each deck section for decades to come.
“It has been a tremendous team effort ever since we lifted the first deck section in October 2015.”