3D printing of buildings between fantasy and reality
To know the future of this technology, we must first look at its past and how it evolved, which reveals the existing challenges and reasons for the application of this technology on a small scale so far, despite all efforts and efforts to activate it in the construction sector.
3D printing techniques generally began in the industrial sector as early as the 1980s, as they were used to make rapid experimental models, and were called additional production – that is, the creation of physical objects by stacking thin layers of material on top. of each other (such as plastic sheets or polymers) These slices are created using robotic directed nozzles that simulate 3D models drawn in engineering design software.
This method differs from ordinary production with the removal method, which depends on the removal of materials from a rigid raw material by drilling or rotation, to obtain the required final shape, as the technology itself is not new, but new is that with the development of robots and materials used in industry by assembly, or what is called Recently, 3D printing has made it possible to produce high-density objects that serve as part of the components of the final product, after their use is limited to manufacturing. of experimental models.
This development in the industrial sector inspired researchers in the construction sector to study the possibility of applying the same method using large-scale machinery to suit the needs of construction and the use of non-reinforced concrete and was the first scientific work. published in the journal Automation in Construction in 2004.
While the technology was in its infancy and in the testing process, a Chinese company called WinSun announced in 2014 that it had printed in just one day ten houses with an area of 200 square meters per house, using durable and recycled cement. materials mixed with chemical additives that solve a fundamental technical problem for this technology.
This news received a wide media coverage and was well received by some governments, which are now seeing this technology as the future of the construction sector. Despite the company’s credibility, it was able to persuade governments to take the technology seriously and invest in its development. Dubai was one of the first cities to adopt the idea in 2016 in building the office of the future, which it took 17 days to print. its elements at the factory, and two days to install on site. At that time, a lot of research was published and many start-up businesses specializing in 3D printing of buildings were created, all of which contributed to the development of 3D printing, both in terms of robotic technologies and materials used for printing.
The main dilemma faced by this technique is the balance between the opposite properties of the cement material used, i.e., the fluidity of the material and the ease of flow through the printer nozzle, and the speed of its processing to become strong enough. before the top layer. of it is lowered, so that the former does not lose the required stability and shape.
Herein lies the challenge in this difficult balance between fluidity and hardness, as it requires precise control of several factors, including printer speed, temperature and outside humidity, in addition to the mixing of cement and additives used in it. Therefore, the development of 3D printing technology requires expertise from civil engineers and specialists Mechatronics, robotics, artificial intelligence and other disciplines.
For example, our research team in this field at the University of the UAE consists of multidisciplinary professors, including computers, robotics, and mechanical engineering, in addition to the Department of Civil Engineering. Despite all the research efforts around the world, technology remains to this day, in my opinion, in its infancy, and does not arise – as is sometimes hoped – a replacement for the traditional building methods developed by engineers and scientists over the centuries, but what we hope is to be used in the future as a complementary technology, which allows several opportunities and solves some challenges of the sector, which can be summarized in three aspects:
1- Building complex concrete elements using 3D printing technology, making printed concrete molds as alternatives to wooden molds made by carpenters on site, which are difficult to form as any architect would like . It is widely known and the benefit here lies in opening up new horizons for creative architects, who often adhere to square and rectangular shapes to avoid the difficulty of implementing their projects.
2- Construction of non-structural elements, such as partition walls, with innovative thermal insulation mixtures, which are less costly and more efficient than the materials currently used.
3- Printing of building accessories, such as door handles, bathroom and kitchen parts, mechanical connections and others, but this is another field from the printing of large building elements that we are talking about here and comes under the door of industrial printing based on advanced printers using iron and aluminum.
The opportunities offered by 3D printing technology are currently focused on these areas. In terms of aspirations for a qualitative shift in the construction and construction sector to double the speed of construction, reduce its cost and improve its quality in terms of belongs to design and implementation. can be achieved by focusing on prefabricated and modular constructions, and perhaps the Museum of the Future building, which was inaugurated by His Highness Sheikh Mohammed bin Rashid Al Maktoum, God forbid, is a good example of what can be applies. when we outsource most construction operations to factories and limit our on-site efforts to installation and construction.
Hamad Abdullah Al Jasmi * Dr.
* Academic of the Emirates