3D printed concrete buildings are one of the popular applications of 3D printing in construction. It is a 3D printing technology that makes use of 3D printers to deposit the concrete material one over the other layer by layer to form a building structure.
Concrete 3D printing consumes less time and effort compared to traditional construction methods and hence make the house or building construction affordable.
The general features of concrete 3D printing, 3D concrete printers, and working of 3D printers for building construction are explained in this article.
Features of Concrete 3D Printing
The important features of Concrete 3D concrete printing of buildings are:
The house 3D printing by concrete is mainly conducted by extrusion technology.
The concrete material is pushed through a nozzle of the concrete 3D printer to form layers that print the buildings in 3D.
The concrete 3D printing can print the wall and frames of the building unit, bridges, benches, or any outdoor decors.
Other requirements like electricity, plumbing, and windows are separately installed.
3D printed concrete buildings are easy to make. It can handle intricate geometries.
The 3D printers used for printing are portable that they can be move to many locations.
It is the best choice for mid-sized homes. It is not optimal for building large luxury buildings and structures.
The use of 3D printing technology reduces the overall wastage of material compared to traditional construction methods. Hence 3D construction is an environmentally friendly technique.
In this method, the designs are printed at the spot. Hence avoids the use of molds that, in turn, save time, money, and energy.
Fig.1. 3D Printing in Layers; Image Courtesy: Softpedia News
Concrete 3D Printers
Most of the 3D printers that are available in the market can directly print on the spot. These are mobile 3D printers. These type of 3D printers normally has a crane and robotic arm arrangement. It deposits concrete layer by layer as required.
Some of concrete printers work offsite. These are structural units that are manufactured offsite and bought on-site and assembled.
The 3D printers for building construction can either be a super-size desktop printers which is a gantry type or can be a printer with a rotating mechanical arm.
Fig.2. COBOD BOD2 3D House Printer - Gantry Type; Developed by Printhuset Company, Denmark
How to 3D Concrete Print Building Structure?
The working of 3D concrete printing can be understood by assuming a 3D Printer, for example, FDM 3D Printer, which uses concrete as the printing material.
The concrete 3D printer is controlled by a set of codes, which are machine language. This command directs the print head until the 3D model is constructed.
Fig.3. A rendering of ICON's Vulcan concrete 3D printer; Source: fortune.com
The concrete 3D printers operate using X, Y, and Z-axis. If the 3D printer is mounted on rails, then the length of the rails used to move the printer back and forth forms the X-axis. The distance between the rails in the opposite direction forms the Y-axis. The height of the pillars that carry the nozzle of the equipment forms the Z-axis.
Every building construction starts with the foundation. Foundations are constructed and made the surface flat so that the 3D printer can place the rails properly and start working from the foundation.
Once the surface for mounting the 3D printer is ready, the next step is to install the printer. The steps involved in the installation and working of 3D printer are:
Install the Rails for the printer. The rails are specially designed for the 3D printer.
Mount the printer on the rails.
The Pillars are set up, and all the three-axis are checked
On the horizontal metal beam, place the nozzle and robotic arm.
Once the installation is complete, the designed concrete mix is bought to the site and connected to the printer's nozzle.
The electrical installations and the reinforcement of the walls are simultaneously implemented during the printing process in a well-coordinated manner.
The concrete used for printing must have sufficient flowability so that the concrete nozzle does not get clogged. The mix hence must be such that it hardens quickly but must efficiently bond with the new layers printed.
Benefits of 3D Printing Concrete Buildings
The use of concrete 3D printing has some real game-changing applications in the construction industry.
3D printers are very fast that they can construct continuously. Some construction companies can print an entire house within 24 hours.
The whole manufacturing process is economical as the only input is the printing material. This reduces the cost of laborers.
3D printers can build a house anywhere at an affordable price which is a better and fast solution for the poor populations.
The buildings constructed by 3D printers are very strong and can withstand natural disasters like tornados. This means than by using a 3D printing process, strong foundations can be created.
Life to incredible structures can be provided by the use of a 3D concrete printing method.
Drawbacks of 3D Printing Concrete Buildings
The future of concrete 3D printing method is promising but faces some challenges in the printer management section.
Some construction projects required the printer to move throughout the project for constructing the structure, which is a difficult task to manage.
It is not always necessary that the printer equipment provide the utmost accuracy and required exterior finish.
Exclusive laws and authorization has to be made for constructing building structure by the method of 3D printing.
