{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,29]],"date-time":"2025-10-29T11:52:48Z","timestamp":1761738768952,"version":"build-2065373602"},"reference-count":36,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2025,10,27]],"date-time":"2025-10-27T00:00:00Z","timestamp":1761523200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Applied Sciences"],"abstract":"<jats:p>As an innovative approach to advancing sustainable construction, this study explores the integration of molybdenum tailings as fine aggregate in 3D-printed mortar. The rheological and mechanical properties of the developed mixtures are systematically investigated. Environmental and economic assessments demonstrate that molybdenum tailings sand exhibits negligible global warming potential (GWP), acidification potential (AP), and cumulative energy demand (CED), completely avoiding the environmental impacts associated with natural sand extraction. Economically, full replacement with molybdenum tailings reduces material costs, as the tailings are typically provided without charge by mining enterprises. Furthermore, the template-free 3D printing technology eliminates formwork-related environmental impacts and simplifies construction processes. Experimental results indicate that mortars with cement-to-sand ratios between 1:1 and 1:2 possess favorable printability, with nozzle movement parameters significantly influencing printed dimensions. While increased molybdenum tailings content reduces mechanical strength, the cement-to-sand ratio exerts a more pronounced effect. The compressive strength of mold-printed and free-printed mortar reaches 55\u201375% and 35\u201355% of conventional mortar, respectively. Anisotropy analysis reveals minimal directional dependence in flexural strength, whereas compressive strength shows clear anisotropy, with X-direction strength measuring approximately 70% of that in the Y direction. This research provides valuable insights into the sustainable design and performance optimization of 3D-printed mortar using industrial byproducts.<\/jats:p>","DOI":"10.3390\/app152111483","type":"journal-article","created":{"date-parts":[[2025,10,28]],"date-time":"2025-10-28T09:16:07Z","timestamp":1761642967000},"page":"11483","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Mechanical Properties of 3D-Printed Molybdenum Tailings Mortar"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9590-9158","authenticated-orcid":false,"given":"Shan","family":"Gao","sequence":"first","affiliation":[{"name":"Shaanxi Key Laboratory of Safety and Durability of Concrete Structures, Xijing University, Xi\u2019an 710123, China"},{"name":"Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education, Harbin Institute of Technology, Harbin 150090, China"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-3507-305X","authenticated-orcid":false,"given":"Tianyu","family":"Li","sequence":"additional","affiliation":[{"name":"Shaanxi Key Laboratory of Safety and Durability of Concrete Structures, Xijing University, Xi\u2019an 710123, China"}]},{"given":"Jian","family":"Yuan","sequence":"additional","affiliation":[{"name":"Academy of Combat Support, Rocket Force University of Engineering, Xi\u2019an 710025, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6745-3141","authenticated-orcid":false,"given":"Tomoya","family":"Nishiwaki","sequence":"additional","affiliation":[{"name":"Department of Architecture and Building Science, Tohoku University, Sendai 980-8576, Japan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5990-8425","authenticated-orcid":false,"given":"Zhenhua","family":"Huang","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, University of North Texas, Denton, TX 76207, USA"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,27]]},"reference":[{"doi-asserted-by":"crossref","unstructured":"AI-Tamimi, A.K., Alqamish, H.H., Khaldoune, A., Alhaidary, H., and Shirvanimogaddam, K. 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