{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,5]],"date-time":"2026-03-05T11:52:59Z","timestamp":1772711579003,"version":"3.50.1"},"reference-count":63,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,3,5]],"date-time":"2026-03-05T00:00:00Z","timestamp":1772668800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Science and Technology Planning Project of Guizhou Province","award":["MS [2025] 244"],"award-info":[{"award-number":["MS [2025] 244"]}]},{"name":"Bijie Science and Technology Project","award":["Bikelianhe [2023] 45"],"award-info":[{"award-number":["Bikelianhe [2023] 45"]}]},{"name":"Bijie Science and Technology Project","award":["[2025] 10"],"award-info":[{"award-number":["[2025] 10"]}]},{"name":"General Project of Bijie Federation of Social Sciences","award":["BSLY-202406"],"award-info":[{"award-number":["BSLY-202406"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Buildings"],"abstract":"<jats:p>Low-carbon and highly printable cementitious materials are crucial for the practical application of extrusion-based three-dimensional concrete printing (3DCP). This study develops and optimizes a one-part alkali-activated concrete suitable for 3D printing through an integrated experimental and evaluation approach. An orthogonal experimental design was employed to investigate the effects of precursor ratio (ground granulated blast-furnace slag, GGBFS, to fly ash, FA), water-to-binder ratio, activator dosage, and retarder content on fresh-state properties, rheological behavior, setting characteristics, and mechanical performance. The optimal mixture was determined using the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) multi-criteria decision method. The mixtures exhibited suitable rheology, with a yield stress of 90\u2013141 Pa and a plastic viscosity of 3.5\u20137.2 Pa\u00b7s, a setting time of 40\u201396 min, and mechanical performance with compressive and flexural strengths of 29\u201371 MPa and 4.2\u20136.9 MPa, respectively. The optimal mixture provided a 95-min printing open time and an acceptable pumping pressure of 1.77 MPa, while full-scale tests confirmed stable extrusion and good print quality. Furthermore, within the defined cradle-to-gate, materials-stage boundary and the adopted inventory factors, the optimized alkali-activated mixture exhibited an embodied CO2 emission of 0.113 kg CO2\/L, which is approximately 61% lower than that of the reference cement-based printable mixture. The proposed approach provides a systematic framework for designing low-carbon, high-performance one-part alkali-activated materials for extrusion-based 3D concrete printing applications.<\/jats:p>","DOI":"10.3390\/buildings16051021","type":"journal-article","created":{"date-parts":[[2026,3,5]],"date-time":"2026-03-05T10:31:14Z","timestamp":1772706674000},"page":"1021","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Optimization of One-Part Alkali-Activated Concrete for Extrusion-Based 3D Printing Through Integrated Performance Evaluation"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3856-9767","authenticated-orcid":false,"given":"Haiyan","family":"Li","sequence":"first","affiliation":[{"name":"School of Civil Engineering, Guizhou University of Engineering Science, Bijie 551700, China"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-2174-0655","authenticated-orcid":false,"given":"Aizhong","family":"Luo","sequence":"additional","affiliation":[{"name":"School of Civil Engineering, Guizhou University of Engineering Science, Bijie 551700, China"}]},{"given":"Xiaozhong","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Civil Engineering, Guizhou University of Engineering Science, Bijie 551700, China"}]},{"given":"Xiaomeng","family":"Ma","sequence":"additional","affiliation":[{"name":"School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan 523808, China"}]},{"given":"Jinsheng","family":"Han","sequence":"additional","affiliation":[{"name":"Faculty of Civil Engineering and Mechanics, Kunming University of Science and Technology, Kunming 650500, China"}]},{"given":"Bo","family":"Cui","sequence":"additional","affiliation":[{"name":"School of Civil Engineering, Guizhou University of Engineering Science, Bijie 551700, China"}]},{"given":"Wei","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Civil Engineering, Guizhou University of Engineering Science, Bijie 551700, China"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,5]]},"reference":[{"key":"ref_1","first-page":"18","article-title":"3D Printed Concrete: A comprehensive review of raw material\u2019s properties, synthesis, performance, and potential field applications","volume":"387","author":"Jindal","year":"2023","journal-title":"Constr. 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