Durability Performance of 3D-Printed Ultra-High Strength Concrete Incorporating Corrosion Inhibitor (2025-10)¶

This paper reports preliminary results on the durability performance of a 3D-printed ultra-high strength concrete (3DP-UHSC). A nitrite-based compound was added at varying dosages (0%, 2%, and 4% by mass of binder) to the developed 3DP-UHSC as a corrosion inhibitor. The effects of the corrosion inhibitor on the workability of fresh mixes and the mechanical properties (compressive and flexural strengths in various directions) of the 3DP-UHSC mixes were studied. Furthermore, the durability performance of the 3DP-UHSC was assessed by conducting porosity, water absorption, and chloride permeability measurements. Mould-cast specimens were also prepared and tested for comparison purposes. The results indicated that the nitrite-based corrosion inhibitor slightly enhanced the flowability of the 3DP-UHSC. Furthermore, the addition of a nitrite-based corrosion inhibitor increased the total charge passed while reducing the porosity and water absorption of the developed 3DP-UHSC. In the Z-direction, the mechanical and durability performances of 3D-UHSC were close to those of mould-cast UHSC.