As we know the construction industry is the most popular and largest service sector in the world. If 3d printing building technology joins hands with it becomes most efficient in some aspects of time and money.
3d printing building technology is similar to other 3d printing technologies in the market but here we have to focus on forces acting on a structure.
From the late 1990’s full research on 3d printing building technology has started. Few patents were registered at the time.
Till now a few companies started constructing houses up to three floors and were successful.
How 3d printing building technology works?
case study 1 (winsen company)
As of mid-2017, the leader in the field (by a number of buildings built) is Chinese company Winsun.
Winsun’s founder, inventor Yihe Ma has developed a technology based on a large 3D printer it states is 10m wide, 6.6m high, and can make very long components, as a conveyor belt can be used as the 3rd axis. The technology is similar to the paste extrusion technology found on consumer desktop 3D printers.
The machine consists of a head that moves in 3 dimensions and extrudes a paste-like material (like continuously squeezing a tube of toothpaste to form a line across your bathroom countertop).
The extrusion is done in horizontal layers, one above the other. The paste then hardens to form a rigid structure in a matter of hours. When you add up all the layers, you can build an object of any shape.
To make a shape, the machine will start with the data file describing the 3D geometry of the part, most often in STL format.
The software will then “slice” the shape into a large number of horizontal layers. The machine will then build the part, starting with the lowermost layer, and adding layers sequentially one above the other till the top of the part is reached.
Most 3D printers work in the similar fashion.
In the case of Winsun, the material used is a paste of cement, sand, and fibers (for tensile strength) mixed with water and chemical additives to give it the right mix of flowability and rapid setting properties.
Winsun does not share detailed pictures of the machine, so it is likely this mixture is prepared in conventional concrete mixers and then pumped into the machine through a flexible pipe.
The mixture needs to set rapidly, If it is still wet when the upper layers are added, the lower layers will squeeze and deform under their weight.
The walls are about 9″ thick and are made of an inner and outer layer of material, connected by zigzagging planes of material.
This is a very clever engineering technology so that In this way, we can able to build walls in any shape.
A key aspect of the method is that 3D printing is done in a factory, not at the site. This differentiates Winsun’s approach from other organizations.
It is similar to the method of precast concrete, where the components are made at factory conditions and transported to the actual site and erected.
Lets look at the first set of 3D printed buildings made by Winsun:
So in this case, Windsun has used factory 3D printing to create the wall panels, and then transported them to the site, assembled them together, and finished off the rest of the construction using conventional methods.
Windsun released this to the press claiming “3D Printers print 10 houses in 24 hours”, but we take that statement with a pinch of salt because what we are interested in is the total construction time.
Conclusion: Overall winsun is a new innovative idea of bringing precast and 3d printing together. But this also has some disadvantages, no building codes, engineering properties have to be considered, etc.
Case study-2 (counter crafting)
Another interesting company in this field is Contour Crafting, a company founded by Dr. Berokh Khoshnevis, based on work he has done at the University of Southern California Schools.
Dr. Khoshnevis at a 3D printing conference and TedX event discussed his technology
Dr. Khoshnevis, a roboticist, has developed a range of interesting technologies that have applications in building construction.
Some of them are:
- contour crafting, a new 3D printing technique that combines the technology of paste extrusion with automated trowelling. The machine extrudes a paste such as a concrete mix and then shapes it with trowels that move along with the printing head (or extruder) while it is in a semi-solid state. Objects are built up in layers that harden into a strong, rigid material.
- Multiple Mobile Robots in Manufacturing Assembly
- The selective inhibition sintering process, a new type of 3D printing process.
- A 3D printer for NASA to construct buildings on the moon that uses regolith or moon soil as the primary building material
Contour Crafting is now working on 3D print houses. In their approach, the machine is placed on the site and is bigger than the actual house.
It is mounted on a gantry crane system and will use a range of robots to build all the house systems, including electrical and plumbing systems.
Conclusion: In contour crafting the equipment has to be taken to the site and a separate track has to be provided and the rest of the things are similar to what we discussed in winsun technologies.
3d printing building technology is the future?
The answer is yes because with an increase in population we need to construct a large number of houses for the living.
The scope and research in this 3d printing building technology are tremendous and have huge opportunities. All the companies that we discussed in this article are in the early stages of their success and there is a need for more research and development.
The main advantages are:
- Cost: The total cost of the building will tremendously decrease with 3d printing building technology, As the raw materials and cost of the labors are excluded the total cost will reduce up to 80%.
- Construction waste: 3d printing uses less energy in projects, so no extra material being produced thus wastage is reduced.
- Design shape: As this machine works with the instructions of a computer shapes, and sizes are precise.
- Time: construction time is the most important aspect of efficiency. This 3d printing building technology reduces lots of time.
- Building codes: There were no regulations and standards regarding electrical, plumbing, safety, etc.
- Material types: As of now we have to use only concrete and plastic. otherwise conventional methods are preferred If you want to construct with steel and wood.
- The buildings are not actual fire and earthquake resistant.
What do you think the future technology might be? comment below