3D Printing with Concrete
The current trend in single home residential development is to use prefabricated kits that allow little flexibility, but the price point is more affordable due to uniform design. Entire walls and sections of buildings can be prefabricated in a climate controlled factory and then shipped on location for quick erection and finishing.
The additive manufacturing industry approaches this problem from a different point of view: instead of bringing ready sections to the building site, why not bring the factory to the building site instead?
Building in concrete has traditionally meant building the mould, after which the concrete is poured in under controlled conditions to avoid air bubbles that might weaken the structure. After the pouring the concrete needs to dry in controlled conditions, too wet or dry; hot or cold; all variables that will affect the strength and stability of the finished concrete build. Larger the build, the longer time it takes to dry. Once the concrete is dry, the mould can be removed, but often the mould will get damaged or destroyed by the process, thereby making it challenging to use same designs repeatedly.
With 3D printing, there is no need to build a mould; instead the concrete is printed in thin layers that will dry faster than when using traditional pouring methods. Shapes and designs previously difficult to achieve and replicate such as round curves can now be used with ease and confidence. 3D printing can also create hollow cavities that can be filled with insulation materials for sound and climate proofing. When creating multiples of the same blueprint, there is often a need for revision of plans between units as plans get adjusted to the unique challenges of each project. Minor revisions can easily be amended into the blueprints when building with 3D printing.
From the enviromental point of view, 3D printing concrete is vastly better than pouring it. Less raw material can be used, and the probability of mistakes is much lower due to the computer-controlled nature of 3D printing. Also, due to the quick-drying nature of printed concrete, there is no need for extended periode of using heater/dryers to maintain optimal drying climate as with the poured concrete.
Benefits using this building method
It offers significant benefits including:
Lower materials consumption since wall structures can be topologically optimized and partially hollow
Less building waste, no need for large-scale concrete moulds or formwork
Faster building times when compared to laying bricks or concrete moulding
Greater degree of design freedom, able to produce geometries (curves, hollows, etc.) that traditional concrete pouring can’t
Higher productivity (it can print 24/7)
Lower need for human physical labor
Reducing CO2 emissions and raw material waste with 3D printing concrete is part of our bigger mission of building a more sustainable future. Another facet of making a better future is also including the well-being of humans. Robots can work ceaselessly, and do all the heavy lifting, redusing strain and stress on human labourers.
3D Printing Head
The main innovation behind 3D printing concrete is the 3D printing head, which extrudes concrete in controlled shapes, speeds and angles. Mounted on a gantry or a mobile frame, the head delivers just the right amount of concrete to just the right spot as specificed in the building blueprints.
The printing head
Controls the speed of the flow of the concrete
Allows imaginative shapes
Consumable parts are few, and easily replaced
Computer controlled; including speed, shape and rotation
Easily adaptable to different types of concrete and additives
Easy cleaning both during and after use
Creative 3D Concrete Prints
The main advantages of 3D printing versus traditional construction techniques are the possibility to create complex forms, a substantial reduction of construction time and costs, and replicability.