Hardened Properties of 3D Printable’One-Part’Geopolymer for Construction Applications

摘要

This paper reports the hardened properties of an extrusion-based 3D printable’one-part’geopolymer for construction applications.To date,all of the 3D printable geopolymers reported in the literature had’two-part’mix formulations,made by using liquid activators.In contrast,the 3D printable geopolymer developed in this study has a’one-part’(just-add-water)mix formulation,made by using a small amount of solid activator instead of the commonly used liquid activators.Handling a small amount of solid activators instead of large quantities of user-hostile liquid activators significantly enhances commercial viability and large-scale application of the 3D printable geopolymers in construction industry.Effects of print-time interval on the inter-layer strength,along with compressive and flexural strengths of the developed 3D printed’one-part’geopolymer in different directions were investigated.Specimens were printed with 2 and 15 min delay times(print-time intervals).Compressive,flexural and inter-layer strengths of the 3D printed’one-part’geopolymer were measured.The results showed that the print-time interval had a significant effect on the inter-layer strength of the 3D printed’one-part’geopolymer.However,the effect of the print-time interval on the compressive and flexural strengths of the 3D printed’one-part’geopolymer was negligible.The results also showed that the compressive and flexural strengths of the 3D printed’one-part’geopolymer depended on the loading direction.