Engineers at MIT have proven Leonardo da Vinci correct yet again, this time involving his design for what would have been at the time a revolutionary bridge design. Although clients rejected da Vinci’s work at the time, over 500 years later, the researchers have proven that his bridge would have worked.
In 1502 Sultan Bayezid II wished to join Istanbul with Galata by means of a bridge across the Golden Horn inlet. The Golden Horn had been bridged by Justinian the Great in the 6th century, but the Sultan was more ambitious, wishing to span it at a wider point, closer to the two cities’ centers.
Leonard da Vinci submitted a solution to the engineering challenge, producing a design to span the Horn in a single arch, tall enough to allow the ships of the day to sail underneath. Had the Sultan approved the idea it would have been the longest bridge span in the world at the time.
MIT graduate student Karly Bast worked with a team of engineering academics to finally bring to life a faithful 1-to-500 scale model of da Vinci’s famously rejected bridge design, putting the Renaissance man’s long-questioned geometry to the test by slicing the complex shapes into 126 individual blocks, then assembling them with only the force of gravity. The group, which presented its work this week in Barcelona, relied on the sketches and descriptions found in da Vinci’s letter bidding for the job, along with their own analysis of the era’s construction methods.
The structure is held together only by compression — the MIT team wanted to show that the forces were all being transferred within the structure, said Bast. “When we put it in, we had to squeeze it in.”
Bast said she had her doubts, but when she put the keystone in, she realized it was going to work. When the group took the scaffolding out, the bridge stayed up.
“It’s the power of geometry,” she said.