How 3D concrete technology could be a game changer

When Fosters + Partners announced in 2013 it was exploring the possibilities of 3D printed buildings on the moon using lunar soil, the concept of 3D printed buildings as a viable commercial alternative to current construction techniques was one step closer to reality writes Martin Liska, Research and Development Manager, Sika. Five years later, this ‘disruptive technology', a term defined by American scholar Clayton Christensen, may well still be in its infancy, but remains on track to being a game-changer in the construction industry with buildings and their components having the potential to quite literally raise themselves.

The digitisation of the construction industry is changing every aspect of construction and the entire lifecycle of a building from design to maintenance. As part of this, 3D concrete printing is just one of the new tools for architects and contractors to change the rules of the game and allow a more efficient and sustainable design. The technology may not yet be at the point where we can build high spec homes or fifty storey buildings but in its infancy it is showing to have remarkable technical, economical as well as sustainability potential.

If 3D concrete printing is to compete with traditional and economical construction methods, then structures need to be printed efficiently. As a 3D concrete printing pioneer, Sika has consolidated all the technologies and knowledge resulting in a developed complex system which ensures that concrete is printed rapidly, inexpensively and precisely.  The system includes the robotics, the Sika Pulsement process control system, the Sika MiniShot extrusion system, 3D mortar system and Sika ViscoCrete® technology.

 One of the major parts of the robotics system is the print head developed by the Sika 3D research team. It is a high performance tool that ensures an efficient printing process through precise management of not only the head movement, but also with the 3D mortar system and the ViscoCrete technology, the properties of the extruded material. Consistence, colour, strength rate development, dimensional stability and durability of the 3D printed concrete are controlled through a tailored selection and dosage of raw materials and proprietary additives.

The concrete extruded through the print head then creates building components layer-by-layer. The material cures within seconds and bonds with the layer placed previously. This way, conventional as well as complex shapes can be constructed rapidly with the highest efficiency of the material use. This allows for the realisation of previously inconceivable architecture, from dynamic curves to futuristic interlinked structures, all of which can be printed directly and efficiently from digital plans.

3D printing does not require formwork or any additional equipment as the concrete is directly moulded into the construction. It is therefore possible to print concrete quickly and competitively.

3D printing offers a wealth of sustainability benefits, directly fulfilling one of Sika's core values. The process aims to significantly increase the speed of construction and eliminate waste through utilisation of virtually all material extruded from the printing head.

The efficient use of materials is such that they become multifunctional; they are not only strong enough to support the structure, but act as an effective insulation in the case hollow wall segments are 3D printed - thus achieving more with less.

The method will allow for building bespoke houses available for the wider market, addressing, for example, the ever-increasing need for housing at a competitive price. 3D printing will also be dependent on fewer logistical processes and a shorter supply chain, both contributing to a faster design and construction time.

The construction industry has a reputation for being slow to adopt innovation and new methods, but the obvious potential and benefits of 3D concrete printing technology is astonishing and should not be underestimated.  Sika is perfectly positioned to lead the field and is prepared to play an important role in the 3D concrete printing market.

Visit: www.sika.co.uk