26 April 2018 10:48
Is the Construction Industry Ready for 3D Printing?
Photo credit: Branch Technology
How ready is the construction industry for 3D printing? With the development of 3D printed buildings, bridges and other constructions, it seems that the construction industry is the latest to adopt 3D printing as a viable manufacturing technology. However, in spite of the visions of 3D printed houses, 3D printing within the construction industry is still a relatively novel approach, and there are a a number of challenges to be overcome before it can be widely adopted. But with technological advances in construction, including robotics and digital fabrication, it is clear that 3D printing has the huge potential to transform the construction industry by reducing production time and costs, while offering design freedom and a high level of sustainability.
How can the construction industry benefit from 3D printing?
While 3D printing for the construction industry is still very much in the early stages, what has already been achieved with the technology points its potential to open up new design possibilities for architects, engineers and designers. One example is the possibility to design buildings with curvilinear walls, and other complex shapes and geometries that may not be possible with traditional construction methods.
Reduced material waste could be another benefit, as additive manufacturing builds parts layer by layer, minimising the amount of material used, particularly when compared to subtractive methods. This could have a positive environmental impact, especially as 3D printing can use recycled materials and allows for the reprocessing of leftover construction material.
Constructing edifices with autonomous or semi-autonomous 3D printers could mean reduced labour-intensive, manual work. The automation of the printing process also means reduced chances of human error or accidents and injuries on construction sites.
3D printing technologies
Depending on the application, several different additive manufacturing methods can be used within construction:
- One of the main methods used is paste extrusion, which involves using a robot arm or crane equipped with a nozzle to extrude the material in paste form onto a build platform. This creates the contours of a building layer-by-layer, with the process of material extrusion resembling the FDM process. An early pioneer of this extrusion process for the construction industry is Bherokh Khoshnevis, the founder of Contour Crafting, whose technology offers a range of materials, including concrete, ceramics and polymers. The ambitions for the application of the technology go even beyond terrestrial constructions to building in space.
- Wire Arc Additive Manufacturing (WAAM) is a method used for metal applications. It works by melting wire with an electric arc which then constructs the metal structure with the help of a robotic welder or drip feeder. A range of metals can be produced, such as aluminium, steel and titanium, and the technology can be utilised to manufacture large structures. One such example of the possibilities of this method is MX3D’s steel bridge.
- Binder jetting can also be used in construction. Binder jetting works by applying a liquid binding agent onto layers of powder material, thereby bonding it. A solid object is produced as the process is repeated layer by layer.
3D printing has already been used in a range of constructions, pushing the boundaries of what can be achieved with the technology.
Above: Dubai’s “Office of the Future” – constructed using 3D printing
In recent years, several companies have developed methods of constructing buildings using 3D printing technology. One such example is China-based company, Winsun, which has produced large-scale constructions, such as a five-story apartment block and a 12,000-square-foot (1,100-square-meter) villa. Using a large printer – more than 100 metres long – hollow walls made of cement, sand, and fibers mixture were created. The walls were transported to the construction site, reinforced and assembled. The disruptive potential of such a method could lead to significant savings in time, labour and materials.
Advances in the development of building-scale 3D printing have also been made by researchers at MIT, who designed Digital Construction Platform – an extrusion-based system capable of 3D printing the basic structure of a building. The free-moving system has a precise robotic arm, which extrudes a material and forms structures of any shape.
The Dubai Future Foundation office building is yet another of Winsun’s projects. Constructed in only 17 days, it is the first 3D printed, fully functional office building.
The construction of bridges using 3D printing is yet another application within the construction industry. Madrid is a home to the first 3D printed concrete bridge, while the Netherlands has seen the construction of an 8 metre-long 3D printed bridge for cyclists. The process took a total of 3 months for robots to create the concrete blocks for the bridge, made up of 800 layers which were then assembled to create the bridge.
Plans are also in place for the construction of the first 3D printed steel bridge in the Netherlands, created by the Dutch robotics startup MX3D. Made out of stainless steel, the curving structure of the bridge showcases the freedom of design provided by additive manufacturing.
The possibility of creating complex, intricate geometries is one of the key benefits of 3D printing, and opens up a completely new scope of creativity for interior designers. A recent example is Bottlepot – a London store with a 3D-printed interior using sustainable materials. This project demonstrates how 3D printing can be used to reduce waste in construction and shape the future for sustainable design.
One of the biggest impact of 3D printing within construction has been in the production of architectural models. 3D printing has revolutionised the architectural modeling process, as it pushes the boundaries of design and allows for quick and cost-effective design changes, saving considerable time and reducing costs in the process.
3D printing has also proved suitable for manufacturing specific components. UK-based contractor, Skanska, is one of the first companies to make 3D printing components into reality. Skanska used 3D printing to manufacture polymer cladding for the roof of the 6 Bevis Marks business-centre in London. This innovative approach has introduced a more advantageous alternative to traditional techniques in terms of time and cost savings.
Challenges to adoption
While additive manufacturing holds huge potential for the construction industry, the technology is still very much in the early stages, and there are still a number of barriers to wider adoption.
- One of the key issues is that of quality control. Regulation for construction is unsurprisingly stringent, and the new technologies and materials offered by additive manufacturing must be incorporated into building standards.
- Furthermore, additive manufacturing requires experienced operators and designers, meaning investment in training to make the most of automated technology and software skills, in order to meet new industrial requirements.
- Another barrier overcome is the limited range of construction materials that can be 3D printed, although research is being conducted, particularly with regard to concrete and bio-based renewable materials.
Despite visions of 3D printing large buildings using one printer, additive manufacturing will not replace traditional construction methods – at least not in the short term. Perhaps one of the biggest use cases of AM technology may lie in the production of complex components, such as joints and facades, leveraging the benefits of freedom of design that additive manufacturing offers. What is clear, however, is that the full potential of additive manufacturing for the construction industry is yet to be fully realised.