Three-dimensional (3D) printing technology allows geometric complexity and customization with a significant reduction in the structural environmental impact. Nevertheless, it poses a serious threat to the environment when organic binders are used. Binder jet printing of alkali-activated geopolymer precursor can represent a successful and environmental-friendly alternative.,The present work reports about the successful 3D printing of metakaolin-based alkali-activated concrete, with dimensional integrity and valuable mechanical behavior.,The geometric behavior was studied as a function of alkali activator flow rate, and the minimum geometric deviation with complete saturation was recorded at 103 mg/s. The printed specimen is characterized by a modulus of rupture as high as 4.4 MPa at 135 mg/s.,The 3D printed geopolymer-based concrete can be potentially used in a wide range of structural applications from construction to thermal insulation elements.,The analysis of the 3D geopolymer-based concrete printing system and material conducted in this paper is original.

中文翻译：

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用于建筑应用的地质聚合物混凝土的 3D 打印

三维 (3D) 打印技术允许几何复杂性和定制化，并显着减少结构环境影响。然而，当使用有机粘合剂时，它对环境构成严重威胁。碱活化地质聚合物前驱体的粘合剂喷射打印可以代表一种成功且环保的替代方案。,目前的工作报告了成功 3D 打印偏高岭土基碱活化混凝土, 具有尺寸完整性和有价值的机械行为。,几何行为被研究为碱活化剂流速的函数，完全饱和的最小几何偏差记录为 103 mg/s。打印样品的特征是在 135 mg/s 下的断裂模量高达 4.4 MPa。