A novel biotechnology solution allow us to stabilize sand with the help of sporosarcina pasteurii, a bacterium that contains the enzyme urease. Due to the catalysis of ureum into ammonium and carbonate, by active enzyme urease, the carbonate precipitates as calcium-carbonate crystals of chalk. The stabilizing process takes in total a few days and sand will be transformed into solid s a n d s t o n e

World’s largest 3D-printed building, Dubai

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A gypsum-based material

3D-printed Pavilion, Sandwaves, Saudi Arabia

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Sand-printed installation

3D-printed wall, Museum of the Future, Dubai

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Sand

load-bearing capabilities and potential durability

3D-printed wall, Museum of the Future, Dubai

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the wall can be ground down and reprinted up to eight times without compromising its structural integrity.

World’s largest 3D-printed concrete bridge, Shanghai

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A composite of polyethylene fiber concrete and admixtures.

Gaia 3D-printed house

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Bio-degradable material: Soil and waste from rice production

The New Raw

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Upcycled marine plastic waste

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Thrice-recycled plastic

The New Raw

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Transforming plastic waste into raw material for 3D printing.

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The size of the plastic flake is 4-7mm. 

Crushed Fruit Basket | PP INJ

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Crushed Car Bumper | PP

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Beeah, Sharjah

1. Replacing nature sand with 100% recycled sand not only decreases the initial fluidity of printing mortar but also increases its losing rate of fluidity, which thereafter shortens its printability window. This is not conducive to the practical printing of the recycled mortar.

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• When additional and suitable sodium gluconate is added into the printing mortar with 100% recycled sand, this mortar on the one hand can satisfy the requirements of printability and obtain a longer printability window. On the other hand, it keeps a much higher green strength at early ages than the mortar with 100% natural sand, which is beneficial for the bottom printed filament bearing more load in shorter time, thus contributing to the realization of continuous 3D printing.

Using industrial 3D printing with silica sand, the presented system enables significant weight reduction of up to 70% when compared to conventional concrete floor slabs, by placing the 3D printed material in key structural areas and by externalising tension forces.

The use of additive manufacturing technologies has the potential to overcome those limitations and to expand the range of bio-cement applications. In the present work an automated process for the production of spatial structures has been developed, in which sand and urease active calcium carbonate powder were selectively deposited within a print volume and treated with a cementation solution. This method provided conditions for calcite precipitation in the powder-containing areas, whereas areas of pure sand served as removable support structure allowing improved fluid exchange. The 3D printed structure was geometrically stable and had sharply defined boundaries. Compressive strength tests on cylindrical specimens showed that the used powder-sand mix was suitable for the production of high-strength bio-cemented material. The present work demonstrates an application of bio-cement in an additive manufacturing process, that can potentially be used to produce resource efficient sustainable building components.

This paper presents the influences of nano-CaCO3 (NC) on the fresh-state and hardened performances of 3D printing cementitious materials (3DPC) with limestone powder (LS). The LS was added at a rate of 15%, while 0, 1, 2, and 3% NC as a partial replacement for LS. Results show that the addition of NC accelerates the hydration reaction of Portland cement through nucleation. Besides, 15% LS increased the fluidity and vertical displacement but decreased the yield stress and green strength of fresh-state 3DPC.

These results revealed that the green strength was significantly related to the yield stress of fresh-state 3DPC with NC. The higher yield stress resulted in higher green strength.