{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:34:08Z","timestamp":1760060048588,"version":"build-2065373602"},"reference-count":42,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2025,7,30]],"date-time":"2025-07-30T00:00:00Z","timestamp":1753833600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Acci\u00f3n 2 Plan Operativo de Apoyo a la TCEE 2022\u2014O.T.R.I. (UJAEN)","award":["UIDB\/50011\/2020","UIDP\/50011\/2020","LA\/P\/0006\/2020","88887.977105\/2024-00"],"award-info":[{"award-number":["UIDB\/50011\/2020","UIDP\/50011\/2020","LA\/P\/0006\/2020","88887.977105\/2024-00"]}]},{"name":"EDUJA fellowship program from the University of Ja\u00e9n","award":["UIDB\/50011\/2020","UIDP\/50011\/2020","LA\/P\/0006\/2020","88887.977105\/2024-00"],"award-info":[{"award-number":["UIDB\/50011\/2020","UIDP\/50011\/2020","LA\/P\/0006\/2020","88887.977105\/2024-00"]}]},{"name":"CICECO\u2014Aveiro Institute of Materials","award":["UIDB\/50011\/2020","UIDP\/50011\/2020","LA\/P\/0006\/2020","88887.977105\/2024-00"],"award-info":[{"award-number":["UIDB\/50011\/2020","UIDP\/50011\/2020","LA\/P\/0006\/2020","88887.977105\/2024-00"]}]},{"name":"national funds through the FCT\/MCTES (PIDDAC)","award":["UIDB\/50011\/2020","UIDP\/50011\/2020","LA\/P\/0006\/2020","88887.977105\/2024-00"],"award-info":[{"award-number":["UIDB\/50011\/2020","UIDP\/50011\/2020","LA\/P\/0006\/2020","88887.977105\/2024-00"]}]},{"name":"Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior\u2013Brasil (CAPES) through the CAPES\/PRINT fellowship program","award":["UIDB\/50011\/2020","UIDP\/50011\/2020","LA\/P\/0006\/2020","88887.977105\/2024-00"],"award-info":[{"award-number":["UIDB\/50011\/2020","UIDP\/50011\/2020","LA\/P\/0006\/2020","88887.977105\/2024-00"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>The use of 3D printing holds significant promise to transform the construction industry by enabling automation and customization, although key challenges remain\u2014particularly the control of fresh-state rheology. This study presents a novel formulation that combines potassium-rich biomass fly ash (BFAK) with an air-entraining plasticizer (APA) to optimize the rheological behavior, hydration kinetics, and structural performance of mortars tailored for extrusion-based 3D printing. The results demonstrate that BFAK enhances the yield stress and thixotropy increases, contributing to improved structural stability after extrusion. In parallel, the APA adjusts the viscosity and facilitates material flow through the nozzle. Isothermal calorimetry reveals that BFAK modifies the hydration kinetics, increasing the intensity and delaying the occurrence of the main hydration peak due to the formation of secondary sulfate phases such as Aphthitalite [(K3Na(SO4)2)]. This behavior leads to an extended setting time, which can be modulated by APA to ensure a controlled processing window. Flowability tests show that BFAK reduces the spread diameter, improving cohesion without causing excessive dispersion. Calibration cylinder tests confirm that the formulation with 1.5% APA and 2% BFAK achieves the maximum printable height (35 cm), reflecting superior buildability and load-bearing capacity. These findings underscore the novelty of combining BFAK and APA as a strategy to overcome current rheological limitations in digital construction. The synergistic effect between both additives provides tailored fresh-state properties and structural reliability, advancing the development of a sustainable SMC and printable cementitious materials.<\/jats:p>","DOI":"10.3390\/ma18153564","type":"journal-article","created":{"date-parts":[[2025,7,30]],"date-time":"2025-07-30T07:37:23Z","timestamp":1753861043000},"page":"3564","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Optimized Mortar Formulations for 3D Printing: A Rheological Study of Cementitious Pastes Incorporating Potassium-Rich Biomass Fly Ash Wastes"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-1596-359X","authenticated-orcid":false,"given":"Ra\u00fal","family":"Vico Lujano","sequence":"first","affiliation":[{"name":"Department of Chemical, Environmental and Materials Engineering, Higher Polytechnic School of Ja\u00e9n, University of Ja\u00e9n, 23071 Ja\u00e9n, Spain"},{"name":"Research and Develoment Department, Cementos La Cruz, 30640 Abanilla, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6912-9844","authenticated-orcid":false,"given":"Luis","family":"P\u00e9rez Villarejo","sequence":"additional","affiliation":[{"name":"Department of Chemical, Environmental, and Materials Engineering, Higher Polytechnic School of Linares, University of Ja\u00e9n, Campus Cient\u00edfico-Tecnol\u00f3gico, 23700 Linares, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5698-9135","authenticated-orcid":false,"given":"Rui","family":"Novais","sequence":"additional","affiliation":[{"name":"Department of Materials and Ceramic Engineering, CICECO-Aveiro Institute of Materials, University of Aveiro, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7581-7117","authenticated-orcid":false,"given":"Pilar","family":"Torrano","sequence":"additional","affiliation":[{"name":"Research and Develoment Department, Cementos La Cruz, 30640 Abanilla, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4399-6293","authenticated-orcid":false,"given":"Jo\u00e3o","family":"Rodrigues Neto","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Federal University of Santa Catarina, Florian\u00f3polis 88040-900, SC, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4782-1685","authenticated-orcid":false,"given":"Jo\u00e3o","family":"Labrincha","sequence":"additional","affiliation":[{"name":"Department of Materials and Ceramic Engineering, CICECO-Aveiro Institute of Materials, University of Aveiro, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Bravo, M., Silva, R.V., and Duarte, A.P. 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