A 03

Extrusion of Near-Nozzle Mixed Concrete –Individually Graded in Density and in Rate of 3D Fibre Reinforcement

Prof. Dr.-Ing. Christoph Gehlen, Project Leader
Prof. Dr.-Ing. Johannes Fottner, Project Leader

M. Sc. Maximilian Dahlenburg
M. Sc. Maximilian Hechtl
Dipl.-Ing. Stephan Kessler
Dr.-Ing. Thomas Kränkel
M. Sc. Carla Matthäus
M. Sc. Yuan Tan

Summary of A 03

The gradation of material properties in concrete extrusion represents a particular challenge. Therefore, an innovative near-nozzle mixing system is being developed in A03 which enables immediate gradation of the fibre content and the density ranging from normal to lightweight concrete. Furthermore, in combination with insertion of vertical reinforcement over several layers a 3D transmission of tensile and flexural forces in the structure can be achieved. Thus, material properties, such as thermal conductivity and strength, can be precisely adjusted in the component.

Prof. Dr.-Ing. Christoph Gehlen

head of cbm and project leader in project A03. He instructs and advises the academic staff regarding additive manufacturing and concrete technological questions. He is responsible for the coordination and quality control of all work of cbm.

gehlen(at)tum.de

Prof. Dr.-Ing. Johannes Fottner

project leader in A03. He instructs and supports the academic staff regarding bulk conveying
and machine design questions.

j.fottner(at)tum.de

M. Sc. Maximilian Dahlenburg

Expert in mechanical engineering specialization development and construction. Responsible for the construction and optimization of the continuous mixing system, the material supply system and the material discharge system.

maximilian.dahlenburg(at)tum.de

M. Sc. Maximilian Hechtl

is a research associate at the Working group of Prof. Dr.-Ing. Christoph Gehlen. Expert in material development of Extrusion Concrete for additive manufacturing.

m.hechtl(at)tum.de

Dipl.-Ing. Stephan Kessler

head of the workgroup bulk conveying and supports Prof. Fottner in leading project A03.
He instructs and supports the acad. staff regarding DEM-solutions, 3D-CAD design and virtual prototyping.

stephan.kessler(at)tum.de

Dr.-Ing. Thomas Kränkel

head of the workgroup concrete technology and assists Prof. Gehlen in leading project
A03. He instructs and supports the academic staff regarding AM and concrete technological questions.

thomas.kraenkel(at)tum.de

M. Sc. Carla Matthäus

expert in AM by extrusion of concrete, rheological questions and material
development. She is responsible for all research regarding extrusion, material development and testing.

c.matthaeus@tum.de

M. Sc. Yuan Tan

yuan.tan(at)tum.de

2020 | Matthäus, C.; Kofler, N.; Kränkel, T.; Weger, D.; Gehlen, C.: Interlayer Reinforcement Combined with Fiber Reinforcement for Extruded Lightweight Mortar Elements. In: Materials 2020, 13, 4778, 2020. https://doi.org/10.3390/ma13214778.

2019 | Rößler, T.; Richter, C.; Katterfeld, A.; Will, F.: Development of a standard calibration procedure for the DEM parameters of cohesionless bulk materials part I - solving the problem of ambiguous parameter combinations. In: Powder technology, Vol. 343, pp. 803-812.

2019 | Rößler, T.; Katterfeld, A.: DEM parameter calibration of cohesive bulk materials using a simple angle of repose test. In: Particuology.

2018 | Pierre, A.; Weger, D.; Perrot, A.; Lowke, D.: Penetration of cement pastes into sand packings during 3D printing: analytical and experimental study. In: Mater. Struct., Vol. 51:22.

2016 | Rackl, M.; Günthner, W. (fml): Experimental investigation on the influence of different grades of wood chips on screw feeding performance. In: Biom. and Bioe., Vol. 88.

2016 | Weger, D.; Lowke, D.; Gehlen, C.: 3D printing of concrete structures using the selective binding method - Effect of concrete technology on contour precision and compressive strength. In: Proc. of 11th fib Int. PhD Symp. in Civ. Eng., Tokyo.

2011 | Stengel, T.; Lin, X.; Schießl, P.; Gehlen, C.: Tailormade Steel Fibre Reinforced Ultra High Performance Concrete – Single Fibre Pull-Out, Bending Capacity and Fracture Toughness. In: Proc. of HPFRCC 6.

2010 | Kränkel, T.; Lowke, D.; Gehlen, C.: Semi- Flowable SCC for Horizontal Slipform Construction. In: Proc. of SCC, Montreal.

2002 | Günthner, W.; Fottner, J.; Rong, O.: Empirische Entwicklung von Kenngrößen zur Auslegung von Hochleistungs-Schneckenförderern für Schuttgut. In: Technical Report, LS fml, Garching.

Matthäus, C.; Weger, D.; Kränkel, T.; Santos Carvalho, L.; Gehlen, C.: Extrusion of lightweight concrete: rheological investigations. in: Proc. of RheoCon, Dresden, accepted.