Construction industry, the only industry still does things manually.
Even in the 21st century, to build a house right now is still a slow, labour-intensive, dangerous process, and almost always over-budget. Unlike the motoring or technology industries which use automated production methods to complete routine construction tasks, housing construction is one of the only industry that still does things manually till now, as said by Professor Khoshnevis from USC.
It is time to change. With the achievement of the research in 3D printing filed, Professor Khoshnevis scaled up 3D printing to make this technology being able to construct buildings by using a process called Contour Crafting. He hope to use this method to improve the basic concept of house construction so that it was accessible to everyone, because with better shelter comes a more civilized society.
How does 3D printer work to print a house?
Here is how 3D printing works to “print” a house:
A CAD design is sent to a large-scale 3D printer that is mounted to a block of land. The printer lays out the concrete-like foundation of the home through a nozzle that can move anywhere on the property. Like any 3D print-out, the house is made layer-by-layer and reinforced with various materials — like electrical, plumbing and communication infrastructure — as the build progresses.
The process is super fast. In a TED presentation, Prof. Khoshnevis said that “we anticipate that an average house, like 2500 square foot house, can be built in about 20 hours from a custom design”.
As for the material used as the “printer ink”, concrete is the solution. The concrete used in the 3D house printer is a mixture of concrete and fibre polymers, meaning that it is more than three times stronger than traditional concrete used in today’s houses. The traditional concrete can withstand roughly 3000 pounds per square inch of pressure, while the new printed concrete can withstand around 10,000 pounds per square inch.
Is it the future of cementitious materials in construction industry?
Professor Khoshnevis says the method could be used to construct emergency or low-income housing. What is more, the concept is currently being supported by NASA so that the space agency can one day be used to build a colony on the Moon, and perhaps on the Mars, who knows.
As a cement researcher, I think the method is really revolutional in the construction industry, even just consider it from the theoretical concept. If the method is quite popular in the future, does it mean cementitious materials are the future of construction materials compared with steel? since the mixture “concrete” is the main material in the 3D printing machine used as “printing ink”.