3D printing technology propels intelligent construction

Photo taken on Aug. 30, 2021 shows the 3D-printed park at the Shenzhen World Exhibition and Convention Center in south China. (China MCC20 Group Corp., Ltd./Handout via Xinhua)

SHENZHEN, Sept. 9 (Xinhua) -- A 3D-printed park with a total area of 5,523 square meters and a greening rate of 88 percent was recently unveiled at the Shenzhen World Exhibition and Convention Center in south China.

Sculptures, benches, flower beds, retaining walls and kerbs in the park have all been completed using concrete construction technology of robotic 3D printing, with a self-developed software control platform, printing toolhead and concrete printing materials.

The 3D printing technology has propelled intelligent construction to move from laboratory to the industry. Users can input the digitally designed model into the system, where the digital model will be automatically processed into control signals of the printing equipment. The concrete mixture then reaches the nozzle at the front end of the mechanical arm through the extrusion device and is finally printed under signal control.

According to a report by Askci, a market consultation firm based in Shenzhen, the scale of China's 3D printing industry reached 20.3 billion yuan (3.14 billion U.S. dollars) in 2020, accounting for 24 percent of the global total and an increase of 31 percent compared with 2019. And it is estimated to reach 25.1 billion yuan in 2021, up 24 percent from last year.

As a form of intelligent construction, concrete construction technology of robotic 3D printing boasts great advantages, said Xu Weiguo, professor at the School of Architecture of Tsinghua University, who led the technical support team.

The technology saves time and human effort, Xu said, adding that the park was constructed in just two and a half months.

It is also environment friendly. For example, the machine-made sand, one of the recyclable construction materials used in the concrete mixture, is made from waste grains of sand, he said.

Compared with reinforced concrete, 3D printing is relatively cheap since the building simulation stage will solve technical problems in advance and come up with the optimum construction method, Xu added.

Xu and his team have explored intelligent construction in other formats as well. They have attempted to print huts that can be opened and closed based on the weather in the suburbs of Zhangjiakou City, a landscape bridge in Shanghai that can accommodate at least four adults per square meter at the same time, and low-cost, sustainable and affordable housing in Africa.

The intelligent construction is still in its infancy, but the digitalization of the construction industry has bright prospects, said Zhang Yu, an official with the construction bureau of Shenzhen's Bao'an district.

With the rising labor costs, manpower will be replaced with robots and intelligent systems, Zhang said, adding the integration of digital design and construction has the potential to redefine the future of architecture.

Xu's team is working on the construction technology and production materials, aiming to achieve breakthroughs in high-performance concrete materials and printing high-rise buildings.