{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,15]],"date-time":"2026-03-15T09:58:16Z","timestamp":1773568696607,"version":"3.50.1"},"reference-count":61,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2021,8,8]],"date-time":"2021-08-08T00:00:00Z","timestamp":1628380800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Guizhou Provincial Science and Technology Foundation","award":["[2020]1Y246"],"award-info":[{"award-number":["[2020]1Y246"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["51669004"],"award-info":[{"award-number":["51669004"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Opening Funds of State Key Laboratory of Building Safety and Built Environment and National Engineering Research Center of Building Technology","award":["BSBE2020-1"],"award-info":[{"award-number":["BSBE2020-1"]}]},{"DOI":"10.13039\/501100004608","name":"Jiangsu Province Natural Science Foundation","doi-asserted-by":"publisher","award":["BK20181187"],"award-info":[{"award-number":["BK20181187"]}],"id":[{"id":"10.13039\/501100004608","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Opening Project of State Key Laboratory of Green Building Materials","award":["2019GBM05"],"award-info":[{"award-number":["2019GBM05"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>This paper focuses on inspecting the influences of anti-foaming agent (AFA) on the performance of 3D printing cementitious materials (3DPC). The mini-slump, spreading diameter, yield stress, and strength of 3DPC were evaluated. Additionally, the air-void content, air-void morphology, and air-void size distribution of mortar with and without 0.05% AFA were assessed through image analysis. The mechanical performance and air-void structure of 3D printed samples were also investigated and compared to that of conventionally mould cast samples. Test results show that an optimal AFA content enables 3DPC to achieve favorable workability and mechanical performance. The addition of AFA exhibits lower air-void content in 3DPC than that of the sample without the AFA addition. This reduction in air-void content is further strengthened by the results of strength analysis. Electron microscope analysis shows that the use of AFA results in the suppressed formation of large air-voids during the process of fresh 3DPC. Moreover, the air-void morphology substantially influenced the mechanical performance of hardened 3DPC.<\/jats:p>","DOI":"10.3390\/ma14164438","type":"journal-article","created":{"date-parts":[[2021,8,8]],"date-time":"2021-08-08T21:49:41Z","timestamp":1628459381000},"page":"4438","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Influences of Air-Voids on the Performance of 3D Printing Cementitious Materials"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9583-4360","authenticated-orcid":false,"given":"Yujun","family":"Che","sequence":"first","affiliation":[{"name":"School of Materials and Architecture Engineering, Guizhou Normal University, Guiyang 550025, China"}]},{"given":"Shengwen","family":"Tang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China"},{"name":"State Key Laboratory of Building Safety and Built Environment, Beijing 100013, China"},{"name":"National Engineering Research Center of Building Technology, Beijing 100053, China"},{"name":"State Key Laboratory of Green Building Materials, China Building Materials Academy, Beijing 100024, China"},{"name":"Suzhou Institute of Wuhan University, Suzhou 215123, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4361-0960","authenticated-orcid":false,"given":"Huashan","family":"Yang","sequence":"additional","affiliation":[{"name":"School of Materials and Architecture Engineering, Guizhou Normal University, Guiyang 550025, China"}]},{"given":"Weiwei","family":"Li","sequence":"additional","affiliation":[{"name":"School of Materials and Architecture Engineering, Guizhou Normal University, Guiyang 550025, China"}]},{"given":"Mengyuan","family":"Shi","sequence":"additional","affiliation":[{"name":"School of Materials and Architecture Engineering, Guizhou Normal University, Guiyang 550025, China"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"132","DOI":"10.1016\/j.cemconres.2019.02.017","article-title":"Hardened properties of 3D printed concrete: The influence of process parameters on interlayer adhesion","volume":"119","author":"Wolfs","year":"2019","journal-title":"Cem. 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