Aug 23, 2018

Concrete 3D Printing – How it Works & What are the Applications

Concrete 3D printing is the shiny new tool in the toolbox of architects and construction companies. It offers a quick and cost-efficient way of building homes. Here's an introduction explaining how concrete 3D printing works, different concrete 3D printing applications, and what the benefits and limitations are.

How Concrete 3D Printing Can Make Housing More Affordable

As you may know, the materials used with 3D printing technology are not just limited to plastic and metal materials. Recent developments in the field of concrete 3D printing proves that there’s an untapped potential in quickly building affordable homes or even entire communities.

There are many benefits of concrete 3D printing. It can be used to produce homes for people that lost their homes in an unfortunate natural disaster, create cheap homes for the homeless, and handle geometries that would be difficult for traditional construction techniques to handle. The list of possibilities goes on and on…

While concrete 3D printing will not fully replace traditional building techniques by tomorrow, the advantages of the technology are undeniable. Designing and building a home can be an expensive and time-consuming task, and that is why concrete 3D printing is an appealing tool for constructors and architects. 

First and foremost, a concrete 3D printer must be quite substantial in size. This is a major challenge that has somewhat hindered the mainstream adoption of concrete 3D printing. However, concrete 3D printers are usually portable, enabling construction in many locations using just one machine. 

At the moment, concrete 3D printing might not be optimal for building large luxury villas, mansions or hotels, but it’s better suited for 3D printing mid-sized homes and other structures at a low price and in a quick manner.

Aside from the low cost and high build speed, another benefit of concrete 3D printing is that nearly no material is wasted during the production process, making it more environmentally friendly than traditional techniques.

Since the architectural design can be 3D printed on the spot, there’s no need for construction companies to make molds to actualize their structures, saving time, money and energy. The modern building design has made features like exposed concrete walls and geometrically complex roofs more popular, both of which presents the perfect opportunity for concrete 3D printing to show what it is truly capable of. 

As more and more successful projects are completed with concrete 3D printers, the legal obstacles that may hinder the technology will ease up as time progresses. Many cities and local municipalities have yet to realize the potential of concrete 3D printing, which means that there could be potential rules/law regarding home construction. But, as time goes, more and more cities will adopt new rules and standards that will support the use of concrete 3D printing technology.

There’s more to a house than four walls and a roof. There are other factors that are important to an inhabitant, such as thermal insulation. To deal with this, companies that specialize in concrete 3D printing are developing mixes of concrete which have a high thermal mass resulting in energy efficiency. Additionally, foam and other insulation materials can be integrated into the concrete walls if needed.

How Does Concrete 3D Printing Work?

To get an idea of how concrete 3D printing works, imagine a gigantic FDM 3D printer that uses concrete instead of plastic filament.

Concrete 3D printers, just like FDM printers, are controlled via g-code, a machine language that works by directing the print head of the 3D printer until the desired 3D model is produced.

Concrete 3D printers and “normal” FDM 3D printers are both similar in some ways and very different in others. In fact, the similarity between plastic FDM printers and concrete printers can be summed up in basically two words: material extrusion. Just like “normal” FDM 3D printers, concrete 3D printers also operate using X, Y and Z axis.

The x-axis of a concrete 3D printer is defined by the length of the rails which are used for moving the printer back and forth. The Y-axis of the concrete 3D printer is defined by the distance between rails on opposite sides and the Z-axis is defined by the height of the pillars which carry the nozzle.

Concrete 3D printers haven’t eliminated the need for construction workers, but it has made their job easier and safer. Professional constructors and builders will still be operating on the field, but alongside the concrete 3D printer.

Obviously, the foundation is needed before houses/buildings can be built above the surface. One of the first steps in preparing the construction site for a concrete 3D printer to arrive is to flatten it so that rails for the printer can be installed. Apart from creating a surface flat, foundations are needed before the process of printing concrete can start. 

As we mentioned above, one of the first steps workers need to do in order to start printing concrete is to deposit specially designed rails for the printer. The next step is to put the printer on the rails, set up the pillars and check all three axes. The nozzle and a robotic arm are located on a horizontal metal beam that’s put across the pillars of the concrete 3D printer.

When the 3D design of the house is ready, concrete comes to the construction field – usually in a normal concrete truck – and is connected to the printer’s nozzle via a big hose.

At this point, you might be asking yourself how electrical installations and reinforcement of the walls are implemented during the concrete 3D printing process. It can all be done during printing thanks to recent developments of the companies which specialize in concrete 3D printing, such as CC Corporation.

Special methods of wall reinforcements are developed by firms that specialize in 3D printing to make bare concrete walls even stronger. Window frames and ceilings are pre-manufactured and installed by a robotic hand that “sits” alongside the nozzle. The concrete that gets printed has to be carefully prepared in order to successfully print buildings.

The goal would be to achieve a concrete mix which is able to provide maximal buildability upon pouring of the concrete and to maximize the flowability of the concrete mix to ensure the nozzle doesn’t get clogged. To say it simply, the goal is to have layers which harden quickly but remain liquid enough to successfully bond with new layers.

To achieve such great performance, the concrete mix must contain perfect amounts of chemicals, such as superplasticizers. Superplasticizers are used to reduce water in a concrete mix. If you want to know more about superplasticizers, learn more here.

Apart from various additives which are put into the concrete mix, manufacturers also improve the strength of the concrete by adding fibers into the mix itself.

Please note that our explanation of how concrete 3D printing works is written in a more general format when compared to detailed descriptions of various concrete printing technologies.

When talking construction 3D printing, people often use abbreviations such as 3DCP (3D construction printing) and LSAM (large scale additive manufacturing). One of the most promising methods of concrete 3D printing is called Contour Crafting (CC).

The applications of CC are seen in the construction of multi-story buildings, but also construction is space! 

All concrete 3D printing technologies are based around the same concept which is similar to “normal” FDM printers, but various concrete 3D printing technologies differ in terms of how reinforcements are installed and many other details such as wall thickness and the geometry of the concrete inside the wall’s “shell”.

All in all, the main idea behind concrete 3D printing is that an architect or designer can convert their 3D blueprints into g-code and send it to the printer. This concrete 3D printer can then immediately turn their idea into reality, significantly reducing the build time and costs in comparison to traditional building techniques.

Applications of Concrete 3D Printing

In this section, we’ll lay down some of the recent and popular applications of concrete 3D printing to give you an idea where the technology is currently used.

Earlier this year, the Texas-based company ICON announced that it had managed to 3D print a 350-square-foot house at an affordable price of $10,000. ICON is working closely with a non-profit organization New Story with a goal of printing homes in El Salvador at $4,000 per home, each being around 600-800 square feet. As they claim, they are working “full throttle” to reduce the price of 3D printed homes, aiming to make housing more affordable all around the world. 

Perhaps you’ve also heard about a man named Andrey Rudenko who 3D printed a castle in his own backyard. Andrey said he always believed that something like that could be done and he was right, he proved his statements with the castle he printed in his backyard. 

One country that is especially fond of using 3D printing to build homes and bridges is the Netherlands. In 2019, the Dutch city  Eindhoven will receive five new houses that will be constructed using special concrete 3D printers. The homes will be inhabited by families, and the biggest of the five houses will include three bedrooms alongside three floors. 

The Netherlands is also home to the world’s first concrete 3D printed bridge for cyclists and pedestrians. This structure was made by the same firm that is providing the equipment that will be used to build the 3D printed houses in Eindhoven. The bridge is made up of several 3D printed pieces of concrete. 

These are just a few examples that showcase how concrete 3D printing is being used. If you’re looking for more examples where concrete 3D printing is used, take a look at our list of the 35 Greatest 3D Printed Houses & Structures

Another great example of how concrete 3D printing is used is provided by the firm called XtreeE, one of the pioneers in the concrete 3D printing sector.

They are 3D printing benches with woven patterns for backyards and parks, but also they do larger-scale projects like house construction. The company also 3D prints concrete facade panels as decor for modern buildings. If you’re interested in XtreeE’s projects, learn more here.

License: The text of "Concrete 3D Printing – How it Works & What are the Applications" by All3DP is licensed under a Creative Commons Attribution 4.0 International License.

Subscribe to updates from All3DP

You are subscribed to updates from All3DP

You can’t subscribe to updates from All3DP. Learn more…Subscribe

You can’t subscribe to updates from All3DP. Learn more…

B719266D-CB2F-4571-9ABD-AFEC8A7D79DCB719266D-CB2F-4571-9ABD-AFEC8A7D79DCB719266D-CB2F-4571-9ABD-AFEC8A7D79DC