The rapid development of 3D printing technology is poised to have a paradigm-changing impact upon myriad facets of the modern economy – with the construction and building sectors perhaps chief amongst them given their intensive material and labour requirements.
3D printing, also frequently referred to as additive manufacturing, involves the precision creation of physical objects in the real world based on digital software designs via the successive deposit of multiple layers of material using a computer-controlled industrial robot.
The technology first emerged in the 1980s with the development of methods for the creation of 3D plastic models using a photo-hardening polymer by Hideo Kodama of Nagoya Municipal Industrial Research Institute in 1981.
Some of the world's leading research bodies had leapt on the bandwagon by the mid-1980s, with Stanford and Carnegie Mellon University experimenting with new depositing methods such as microcasting and spraying of materials.
By the first decade of the new century, the term additive manufacturing had gained currency, referring to the process by which 3D printing sequentially accumulates materials in order to create a finished physical object.
3D printing has truly come into its own since the turn of the decade, with proponents pointing to the near-endless range of potential manufacturing and industrial applications of the new technology.
Much media attention has thus far focused on the potential of 3D printing to create highly detailed and precise small-scale objects such as mechanical parts and machine components.
The technology can be applied across an extremely broad range of dimensions, however, and is increasingly making inroads into the one field of human endeavor which involves the creation of the largest physical assets employed by society – the construction and building industry.
A major pathfinder in this area is Behrokh Khoshnevis, an engineering professor at the University of Southern California and Fellow Member of the National Academy of Inventor.
Khoshnevis’s “contour crafting” is a building printing technology that employs a computer-controlled gantry to first create the walls of a house by depositing successive layers of a rapid-setting concrete-like material – the standard process for additive manufacturing.
Once the walls are “printed” on site, floors and ceilings are then installed by means of the gantry.
Khoshnevis has been working on the project since last decade, claiming in 2010 that the system could produce an entire home within a single day, and cut down on costs by reducing wastage of materials as well as construction time.
On the other side of the pond in the Netherlands, Universe Architecture’s Janjaap Ruijssenaars has been working on plans to print an entire building since the turn of the decade, working with Enrico Dini and his D-Shape printer, one of the world’s largest additive manufacturing devices.
The house designed by Ruijssenaars consists of a cursive, long-form loop structure that is aesthetically provocative and extremely well-suited to the use of a giant 3D printing device for construction purposes.
While the original plan was for the house to be produced in discrete segments that slot together, Ruijssenaars hopes it will eventually be possible for the entire structure to be printed in a single, uninterrupted instance given its organic loop structure, dispensing with the need to produce the roof and flooring separately.
When it comes to more commonplace yet perhaps also more pragmatic building structures, China has leapt to the fore in the use of 3D printers for construction purposes.
The technology harbours especially strong potential in China, which is currently the midst of a building frenzy to accommodate the many millions of people who are flocking to the cities as part of the country’s mass urbanization process.
Jiangsu-based WinSun New Materials last year used its own proprietary 3D printing technology to create a set of 10 basic buildings structures within the space of a single day.
Each of the buildings measured 6.6 metres in height, 10 metres in width and roughly 20 metres in length, for the staggeringly low cost of just US$5,000.
WinSun said the buildings, which had been printed in the Jiangsu city of Suzhou, would be assembled in Shanghai for use as offices by the local government.
The company’s CEO Ma Yihe, a veteran of the additive manufacturing industry who has been involved the technology since last century, said the structures were highly economical and environmentally friendly, given that they employed recycled materials and could be built in such a brief time frame.
The sustainable nature of the process is of particular importance in China given the country’s ongoing struggle with the pollution caused by the industrialization and development process.
“Industrial waste from demolished buildings is damaging our environment, but with 3D printing, we are able to recycle construction waste and turn it into new building materials,” Ma said. “This would create a much safer environment for construction workers and greatly reduce construction costs.”
The material employed by the process consists of a mixture of construction and industrial waste which is ground up and added to a base of fast-hardening cement with a hardening agent.
The 3D printer array itself is just about commensurate in size with the structures it produces, measuring 6.6 metres in height, 10 metres in width and 40 metres in length.
At the start of 2015, Ma grabbed headlines by printing out an entire five-storey apartment building as well as a 1,100 square metre villa for display at the Suzhou Industrial Park.
According to WinSun, the villa cost roughly $161,000 to produce – a low price achieved by reducing construction waste by between 30 and 60 per cent, production time by between 50 and 70 per cent, and labour costs by between 50 and 80 per cent.