Abstract
Conventional approaches to concrete three-dimensional (3-D) printing relies on printing concrete in a straight (linear) print path, with layers overlaid on top of each other. This results in interlayer and interfilament joints being potential weak spots that compromise the mechanical performance. This paper evaluates simple alterations to the print geometry to mitigate some of these effects. A printable mixture with 30% of limestone powder replacing cement (by mass), with a 28-day compressive strength of approximately 70 MPa in the strongest direction is used. S- and 3-shaped print paths are evaluated as alternatives to the linear print path. Staggering of the layers ensures that the interfilament joints do not lie on the same plane along the depth. Flexural strength enhancement is observed when print geometries are changed and/or layers are staggered. The study shows that print geometry modifications mitigate mechanical property reductions attributed to interfilament defects in 3-D concrete printing.
Original language | English (US) |
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Pages (from-to) | 17-30 |
Number of pages | 14 |
Journal | ACI Materials Journal |
Volume | 121 |
Issue number | 2 |
DOIs | |
State | Published - 2024 |
Keywords
- anisotropy
- compressive strength
- flexural strength
- layer geometry
- three-dimensional (3-D) concrete printing
ASJC Scopus subject areas
- Civil and Structural Engineering
- Building and Construction
- General Materials Science