Advances in Sustainable 3D-Printed Geopolymer Concrete (2025-09)¶

This review presents a comprehensive assessment of sustainable 3D-printed geopolymer concrete (3DPG), emphasizing its potential as a low-carbon, eco-efficient alternative to traditional construction materials. The study explores the integration of geopolymer technology with 3D printing to enhance design flexibility, reduce environmental impact, and improve construction efficiency. Key objectives include evaluating the influence of printing parameters and raw materials on fresh properties (flowability, thixotropy, yield stress), mechanical performance (compressive, flexural, tensile strength), and microstructural development. Particular attention is given to interlayer bonding, porosity, shrinkage, and durability characteristics, which are critical for structural reliability. The review also highlights the role of activators, supplementary materials (slag, silica fume, metakaolin), and reinforcement strategies in optimizing performance. Additionally, advanced characterization techniques such as SEM, XRD, and FTIR are discussed for microstructural analysis. From an environmental perspective, the benefits of using industrial byproducts and life cycle impacts of 3DPG are evaluated, supporting its application in next-generation green construction. This study provides valuable insights for researchers and practitioners aiming to develop high-performance, sustainable, and digitally fabricated geopolymer-based structures.