Construction

3D printing offers a variety of technologies that use 3D printing as the main means of constructing buildings or building components. 3D-printing technologies used on a construction scale include extrusion (concrete/cement, wax, foam, and polymers), powder bonding (polymer bonding, reactive bonding, sintering), and additive welding. 3D printing in construction has a wide range of applications in the residential, commercial, industrial, and public sectors. The advantages of these technologies include allowing for more complexity and accuracy, faster construction, lower labor costs, greater functional integration, and less waste.

The first fully finished 3D-printed residential building was built in Yaroslavl, Russia, in 2017. 600 elements of the walls were printed in the shop and assembled on site, followed by the completion of the roof structure and interior decoration for a total area of 2985 square meters (3213 sq. ft.). This project is the first in the world whereby the entire technological cycle had passed on building requirements, from

FIGURE 7.17 Largest 3D-printed building.

design, building permits, registration, to the integration of all engineering systems. The building wasn’t built just for presentation; it’s a real building, with normal families living there today.

Concrete 3D printing has been in progress since the 1990s as a faster and cheaper way to build buildings and other structures. Large 3D printers designed specifically for printing concrete can pour foundations and build walls on site. They can also be used for printing modular concrete parts, which are later installed on the job site.

In 2016, the first pedestrian bridge was printed in 3D in Alcobendas, Madrid, Spain. It was printed in micro-reinforced concrete with a length of 12 meters (39 ft.) and a width of 1.75 meters (5.7 ft.). The bridge illustrates the complexities of nature and has been designed for both parametric (using a set of rules, values, and relationships that guide the design) and computational design, allowing for an optimal distribution of materials while maximizing structural performance.

The first large-scale application of 3D-printing technology in the field of civil engineering in a public space was a landmark in the international construction industry.

3D printing is used to create architectural scale models, allowing a quicker turnaround of the scale model and increasing the overall speed and complexity of the artifacts produced (Figure 7.17).