Students from the Eindhoven University of Technology in the Netherlands are heading to Finland to build the world’s longest ice bridge.
The 65m structure will be based on the Golden Horn Bridge – an unbuilt design created by Leonardo da Vinci in response to a commission from Sultan Bayazid II of the Ottoman Empire, who wanted a crossing over the Bosphorus.
That structure, which would have been the longest single arch ever built, was based on a combination of three geometric principles: the pressed-bow, the parabolic curve and the keystone arch.
The Bridge in Ice uses the same principles, but will express them using 900 tons of ice with a free span of 35m rather than da Vinci’s 240m.
It will be built in Juuka, eastern Finland, over the course of six weeks. When it is finished it will be the main attraction of an ice festival.
A rendering of the ice bridge (Eindhoven University of Technology)
The construction technique uses a balloon mould that is sprayed with water, to which an admixture of paper fibre has been added.
As each layer freezes another is added, until the structure has enough strength to stand without the balloon.
The paper, which composes about 2% of the bridge, makes the ice three times stronger and 10 times more resistant to erosion.
The fibre that will remain after the ice has melted in the spring will be used as compost.
Around 150 students and volunteers will be making the trip to Juuka to build the bridge.
The project is the third "ice project" to be built in Finland by Eindhoven students. In 2014, a team built a 30m-wide ice dome – the world’s largest – in three weeks.
In other wintery news, a hotel made of ice has recently opened in Lapland.
Image: A render of the ice bridge (bridgeinice.com)