A 3D-printed bridge will soon be put in place over a river in an innovation park in Putuo District. The 15-meter S-shaped bridge was made in 35 days by a giant 3D printer. The technique, which is much faster and cleaner than the alternatives, has made the bridge more durable and beautiful, according to Shanghai Mechanized Construction, who created the structure. The bridge will be fully tested before being installed in a park in Taopu Smart City, a business district featuring smart and innovation enterprises. 3D printing, widely used in education, medicine and the automobile industry, is expanding into architecture and construction. Printers can create complicated structures, reduce labor costs and the process causes less pollution. Very little construction waste was produced at the warehouse where the bridge was printed. The bridge is made from ASA, an engineering plastic, with fiber glass to reinforce the structure. The printer mixes and squeezes out the materials layer by layer. It takes eight hours to print a 4-millimeter-thick layer of the bridge structure. According to preliminary tests, every square meter of the bridge can bear 250 kilograms or four adults. It will remain in service for at least three decades and if any part is damaged, a new part can be printed. Tongji University printed two bridge models in July 2017. The bridges, with spans of 4 and 11 meters were used only for display. The SMC team built several miniature bridges, said Chen Xiaoming, the chief engineer of the group. The new bridge will be the first open to pedestrians.