3D Concrete Printing of Solid Wall Cross-Sections with Truckmounted Concrete Pump (2025-01)¶

The 3D concrete printing process offers the potential to replace traditional construction methods, particularly in view of increasing design and quality requirements and the shortage of skilled workers. In collaboration between Ed. ZÜBLIN AG and Putzmeister Holding GmbH, an innovative concrete printing process was developed under the name KARLOS. The process is based on an automated truck-mounted concrete pump that extrudes concrete via a special print head and prints load-bearing walls without formwork or post-compaction. The first real construction project was realized at the end of 2023 on the STRABAG BMTI site in Stuttgart-Weilimdorf in the form of a warehouse. A 10 × 6.5 × 5 m3 warehouse with a total of 35 linear meters of load-bearing and room-enclosing exterior walls and a surrounding parapet was printed. For the KARLOS 3D printing technology, a standard-compliant concrete in accordance with DINEN206-1 i. DIN1045-2 was used for the production of the warehouse. This allowed the 3D-printed walls to be designed in accordance with the specifications of DINEN1992-1-1 Part 12 for load-bearing structures made of unreinforced or lightly reinforced concrete. This procedure was confirmed by various tests, including large-scale tests on components at the MPA Karlsruhe of the Karlsruhe Institute of Technology (KIT), to assess the structural and fire protection properties. The project shows promising potential that will be further exploited in future construction projects.