Printcrete-3D printing of Sustainable Prefabricated Concrete Elements

Printcrete- Towards sustainable 3D concrete printing It’s often claimed that 3D printing in construction – will revolutionize the way we build and live, creating smarter, more sustainable homes and communities.3D printing in construction known in the trade as “3D Printing of Concrete (3DCP)” - uses a combination of materials science, architecture, design, computation, and robotics.

Yet in some respects, it is not as complex as it sounds.

The basic approach of layer-wise construction – where concrete is layered on top of each other to construct a single element using digital fabrication technique.

The true novelty of 3DCP lies in its ability to combine new sustainable and highly efficient materials with design software and robotic technology, to automate and improve processes that have already been proven manually.

In this sense, 3DCP holds many potentially ground-breaking benefits for the Swedish construction industry. 3DCP can produce up to 30% less material waste, reduce use of energy and resources, lower the construction time (up to 70%), permit greater architectural freedom and generate fewer CO₂ emissions over the entire lifecycle of the concrete product as well as reduce labour costs by 20 %.Due to the benefits offered, the question is not whether concrete 3D printing will play a major role in the Swedish construction industry, but just how and when.

Manufacturing process of concrete structures has not improved much over last one hundred years as a lot of manual labor is still used, especially on-site.

The prefabricated concrete production is on the highest level of automatization and is prone to innovation in 3D-printing.

The 3DCP technology has three main critical success factors: the printing material, the printing robot and business models for validation of new technology.This project focusses on the development of material, new digital design procedures, robot, and business models for supply chain and sustainability of the process.

The project consortium: RISE, Lund University (LTH), Royal Institute of Technology (KTH), industry partners (ABB, Adaxis, Cementa, SIKA, UBAB, Benders, Volvo cars) has the expertise to implement 3D printing technology for construction or other applications. The project is organized as follows. First, sustainable concrete developed for validating the 3D printing process is tested.

Second, the designs of prefabricated concrete elements are generated.

Then, 3D printing process is developed that involves design and modification of extrusion print head, nozzle, and material delivery system.

Additionally, 3D printing process is developed that evaluates dynamically placed objects during printing and various sensors for monitoring the printing process.

Furthermore, test cases of prefabricated concrete elements (from building and wastewater management area) are printed in real prefabrication plant; in addition, special test case (from Volvo car test track) is conceptually designed.

Finally, technology potential for digitalization 3DCP is obtained by developing business models for supply chain and sustainability (LCA and LCC).The work summarizes the approach towards to an appropriate material development, 3D printing process development and business models which can harness the power the digital fabrication and overcome the current constraints which are hindering the wide application of 3D concrete printing in Swedish construction industry.

Printcrete will present that 3DCP calls for a holistic design-to-production strategy, and that it has a great potential to change the way we build sustainable Swedish infrastructure.