Title:
Designing Better 3D Printed Concrete: Optimizing Aggregates and Paste Volume
Author(s):
Benjamin Manaugh
Publication:
Web Session
Volume:
Issue:
Appears on pages(s):
Keywords:
DOI:
Date:
10/26/2025
Abstract:
The 3D concrete printing (3DCP) industry has relied on cement-rich mortar to facilitate pumping and ensure rapid development of strength; however, to improve the sustainability and shrinkage performance of printed concrete there must be a transition to mixes with coarse aggregate. To evaluate the printability of these concrete mixes, we used fresh property tests which replicate the effects of pumping, extrusion, and layer build-up. We begin by the applying the ICAR flow tests, which was used to measure the bulk and interfacial rheology for prediction pipe flow. Next, extrusion testing, which was employed to quantify the impact of pipe reducers, stop-starts, and nozzle extrusion. We then characterize the mix stability under pumping particularly the bleed rate. Finally, we the fresh-state strength development was measured with both an ICAR and a handheld shear vane to determine limits on layer height and overlap time. Through collaboration with a 3DPC contractor, these fresh property tests and new mix design principles are connect full-scale 3DPC structures.