Title:
Print Geometry Alterations and Layer Staggering to Enhance Mechanical Properties of Plain and Fiber- Reinforced Three-Dimensional-Printed Concrete
Author(s):
Avinaya Tripathi, Sooraj A. O. Nair, Harshitsinh Chauhan, and Narayanan Neithalath
Publication:
Materials Journal
Volume:
121
Issue:
2
Appears on pages(s):
17-30
Keywords:
anisotropy; compressive strength; flexural strength; layer geometry; three-dimensional (3-D) concrete printing
DOI:
10.14359/51740262
Date:
4/1/2024
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.