Bond Strength in 3D Printed Geopolymer Mortar

3D printing is getting significant attention in the construction industry. This technology, which has been talked for years, is now delivering tangible results, however it is not yet ready for mass production in mainstream construction. Thixotropy material, 3D printer together with 3-dimensional computer model are the key elements required for robust concrete printing. For a freshly printed material, the increase in structural buildup at rest, prior to the placement of a successive layer can result poor interlayer bond strength and therefore, in this paper, we aimed to investigate the structuration effect of a nano-clay modified geopolymer, used for 3D concrete printing. Different structuration rate was achieved by changing molar ratio of activator and experimental results conclude that, there exists an optimum printing zone for different molar ratios, beyond which interlayer bond strength will be very weak.

[1]  Ye Qian,et al.  Experimental and modeling study on the non-linear structural build-up of fresh cement pastes incorporating viscosity modifying admixtures , 2018, Cement and Concrete Research.

[2]  Ming Jen Tan,et al.  Additive manufacturing of geopolymer for sustainable built environment , 2017 .

[3]  J. Hot,et al.  Rheology of geopolymer: Comparative study between portland cement and metakaolin based geopolymer , 2013 .

[4]  Ming Jen Tan,et al.  Experimental study on mix proportion and fresh properties of fly ash based geopolymer for 3D concrete printing , 2018, Ceramics International.

[5]  Kamal H. Khayat,et al.  Bond Strength in Multilayer Casting of Self-Consolidating Concrete , 2017 .

[6]  Kah Fai Leong,et al.  3D printing trends in building and construction industry: a review , 2017 .

[7]  N. Roussel,et al.  Distinct-layer casting of SCC: The mechanical consequences of thixotropy , 2008 .

[8]  Damien Rangeard,et al.  Structural built-up of cement-based materials used for 3D-printing extrusion techniques , 2016 .

[9]  J. Provis,et al.  Designing Precursors for Geopolymer Cements , 2008 .

[10]  Freek Bos,et al.  Additive manufacturing of concrete in construction: potentials and challenges of 3D concrete printing , 2016, International Journal of Civil Engineering and Construction.

[11]  David J. Corr,et al.  The thixotropic behavior of fresh cement asphalt emulsion paste , 2016 .

[12]  Aurélie Favier,et al.  Flow properties of MK-based geopolymer pastes. A comparative study with standard Portland cement pastes. , 2014, Soft matter.

[13]  K. Leong,et al.  3D Bioprinting of Highly Thixotropic Alginate/Methylcellulose Hydrogel with Strong Interface Bonding. , 2017, ACS applied materials & interfaces.

[14]  B. Panda,et al.  Measurement of tensile bond strength of 3D printed geopolymer mortar , 2018 .

[15]  Falk K. Wittel,et al.  Evolution of strength and failure of SCC during early hydration , 2016, 1609.02293.