3D Concrete Printing for Structural Applications

Abstract

Recent years have seen a rapid growth of additive manufacturing methods
for concrete construction. Potential advantages include reduced material
use and cost, reduced labor, mass customization and CO2 footprint
reduction. None of these methods, however, has yet been able to produce
additively manufactured concrete with material properties suitable for
structural applications, i.e. ductility and (flexural) tensile strength.
In order to make additive manufacturing viable as a production method
for structural concrete, a quality leap had to be made. In the project
‘3D Concrete Printing for Structural Applications’, 3 concepts have been
explored to achieve the required structural performance: applying steel
fiber reinforcement to an existing printable concrete mortar,
developing a strain-hardening cementitious composite based on PVA
fibers, and embedding high strength steel cable as reinforcement in the
concrete filament. Whereas the former produced only an increase in
flexural tensile strength, but limited post-peak resistance, the latter
two provided promising strain hardening behavior, thus opening the road
to a wide range of structural applications of 3D printed concrete.