World’s Longest 3D-Printed Concrete Footbridge Bridges Old and New
Emily Pollock posted on February 22, 2019 |
Tsinghua University’s new footbridge takes inspiration from the 1,500 year-old Anji Bridge. (Image courtesy of Tsinghua University.)
A team at Shanghai’s Tsinghua University has built the world’s longest 3D-printed concrete bridge. And, while the bridge is cutting-edge, the team says that it was inspired by China’s oldest standing bridge: the Anji Bridge.
Professor Xu Weiguo’s team unveiled their new bridge, which stretches over a canal in Wisdom Bay Innovation Park, in January. The bridge was 3D-printed by two robotic arms, a process that took just 450 hours split between the two limbs. According to the team, the concrete printing means that its cost was 1/3 lower than a comparable bridge made by more traditional methods. It’s currently the longest concrete 3D-printed bridge in the world, at 26.3 m (approximately 86 feet) long and 3.6 m (approximately 12 feet) wide.
About a thousand kilometers and one and a half thousand years separate it from its inspiration, Anji Bridge. Built by craftsman Li Chun during the Sui Dynasty (starting around AD 605), the bridge is the oldest standing bridge in China today, although the ornamental railings have to be replaced “every 300 to 500 years.” The central arch is made of 28 thin limestone slabs connected with iron dovetail joints.
While the sides of the Anji were made from limestone slabs…