Performance Evaluation of Vertical Auger Extrusion System for Natural Fiber Mortar Composite in 3D Printing Concrete (3DPC)
Danang Murdiyanto, Agus Naba, Dionysius J. D. H. Santjojo, Didik Rahadi Santoso

Brawijaya University, Malang

Abstract

The development of 3D Printing Concrete (3DPC) technology requires a stable, controllable extrusion system capable of handling high-viscosity cementitious composites. This study presents the design and experimental evaluation of a vertical auger-based extrusion system for natural fiber mortar composites in construction-scale additive manufacturing applications. Two material compositions were investigated, namely mortar composite without natural fiber reinforcement and mortar composite reinforced with natural fibers The extrusion system employed a vertical screw mechanism with a nozzle inclination angle of 75 and three rotational speeds of 20, 40, and 60 RPM.
The experimental investigation focused on evaluating motor power characteristics under idle and extrusion loading conditions, extrusion homogeneity, and buildability performance of printed materials. Electrical power consumption was analyzed using voltage and current measurements during extrusion. The results indicate that increasing screw rotational speed significantly increased motor power consumption and extrusion resistance. Furthermore, incorporating natural fibers increased internal friction and flow instability within the extrusion chamber, leading to higher energy demand compared with plain mortar mixtures. Nevertheless, the developed vertical auger system demonstrated stable material conveying capability and acceptable buildability performance for both material compositions.
This study provides an experimental foundation for the future development of closed-loop extrusion control and process optimization in sustainable 3D concrete printing applications using natural fiber reinforced cementitious composites.

Keywords: 3D printing concrete (3DPC)- Vertical auger extrusion- Mortar composite- natural fiber- extrusion power- buildability

Topic: Instrumentation and Computational Physics