TY - JOUR
T1 - Modelling the influence of material and process parameters on Shotcrete 3D Printed strands - cross-section adjustment for automatic robotic manufacturing
AU - Lachmayer, Lukas
AU - Böhler, David
AU - Freund, Niklas
AU - Mai, Inka
AU - Lowke, Dirk
AU - Raatz, Annika
N1 - Publisher Copyright:
© 2022 The Authors
PY - 2023/1
Y1 - 2023/1
N2 - Due to its high interlayer strength and application flexibility, Shotcrete 3D Printing (SC3DP) is a promising method for the additive manufacturing of structural concrete components. The printing process is based on a layer-wise material application, conducted along a pre-designed printing path. However, material batch inhomogeneities and environmental alteration lead to varying concrete properties over the production processes. These material irregularities stochastically affect the layer geometry and thus limit the achievable reproducibility and accuracy. To enhance the process stability and improve the dimensional component quality in case of environmental changes, a reliable mapping between the strand geometry and the process and material parameters is fundamental for systematic cross-section adjustment. In this paper, we present an experimental-based approach for attaining a flexible regression model of the cross-section of Shotcrete 3D Printed concrete strands. The width and height of the layer are chosen for the strand representation, which we considered as the main factors for the printing-path planning. Regarding the modelling parameters, we focus on the volume flow parameters of concrete and air, and on the accelerator dosage. These inertia afflicted parameters can provide a consistent strand geometry, while factors of lower latency such as printing speed or spray distance are conserved for online adaptation. Based on the presented proceeding, an adjustable layer height and width model has been successfully used to predict the strand properties. The production of a medium sized sample wall further proves the applicability to the production process. In addition, we demonstrated that the chosen parameters not only affect the geometry but also the mechanical performance of SC3DP-specimens. This is evaluated based on flexural strength measurements. Given the geometrical and mechanical properties, the study defines applicable limits for the investigated parameters.
AB - Due to its high interlayer strength and application flexibility, Shotcrete 3D Printing (SC3DP) is a promising method for the additive manufacturing of structural concrete components. The printing process is based on a layer-wise material application, conducted along a pre-designed printing path. However, material batch inhomogeneities and environmental alteration lead to varying concrete properties over the production processes. These material irregularities stochastically affect the layer geometry and thus limit the achievable reproducibility and accuracy. To enhance the process stability and improve the dimensional component quality in case of environmental changes, a reliable mapping between the strand geometry and the process and material parameters is fundamental for systematic cross-section adjustment. In this paper, we present an experimental-based approach for attaining a flexible regression model of the cross-section of Shotcrete 3D Printed concrete strands. The width and height of the layer are chosen for the strand representation, which we considered as the main factors for the printing-path planning. Regarding the modelling parameters, we focus on the volume flow parameters of concrete and air, and on the accelerator dosage. These inertia afflicted parameters can provide a consistent strand geometry, while factors of lower latency such as printing speed or spray distance are conserved for online adaptation. Based on the presented proceeding, an adjustable layer height and width model has been successfully used to predict the strand properties. The production of a medium sized sample wall further proves the applicability to the production process. In addition, we demonstrated that the chosen parameters not only affect the geometry but also the mechanical performance of SC3DP-specimens. This is evaluated based on flexural strength measurements. Given the geometrical and mechanical properties, the study defines applicable limits for the investigated parameters.
KW - 3D concrete printing
KW - Additive manufacturing in construction
KW - Flexural strength
KW - Geometry
KW - Material and process parameters
KW - Process control
KW - Robot based manufacturing
KW - Shotcrete 3D printing
UR - http://www.scopus.com/inward/record.url?scp=85140987513&partnerID=8YFLogxK
U2 - 10.1016/j.autcon.2022.104626
DO - 10.1016/j.autcon.2022.104626
M3 - Article
AN - SCOPUS:85140987513
SN - 0926-5805
VL - 145
JO - Automation in Construction
JF - Automation in Construction
M1 - 104626
ER -