Editorial (2025-02)¶

We are pleased to introduce this special issue dedicated to the Emerging Materials for 3D Printing in Construction (3DPC). Despite recent progress in 3DPC, there’san urgent need to develop a suitable 3D printing material that enhances performance while minimizing material usage. The limited choice of printable concrete materials is among several challenges faced by current 3DPC methods. Researchers have extensively studied all types of binder, including alkali-activated and cementitious materials (AACM) to address this issue and create sustainable alternatives to traditional binders like Portland cement. Therefore, a comprehensive review of all types of binder, including AACM performance in 3D-printable concrete for construction is essential. This special issue comprehensively covers all aspects of 3DPC quality assessment, including pros, cons, procedures, delivery, and placement. Unlike the conventional method of pouring concrete into molds, 3DPC application in construction offers advantages such as more design flexibility and savings in cost and time. Overcoming the challenges of limited printable concrete options, innovative techniques are being explored to develop all types of binder, including AACM for 3DPC in construction. These involve using alkali-activated aluminosilicate materials with a significant amount of aluminum (Al) and silicon (Si) in amorphous form as substitutes for traditional binders like OPC. However, the primary focus of this special issue is to compile in-depth research on the behavior and traits of concrete composites based on all types of binder, including AACM for 3D-printed structures. In addition, current research trends also emphasize understanding the financial benefits and environmental impacts of 3DP‘, using all types of binder, including AACM as sustainable ingredients. This special issue covers several selected papers on 3D printing science and technology, including raw materials selection and mix proportion design, workability and rheology, mechanical properties and structural performance, durability and service life, as well as constructability and field applications.