{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,7]],"date-time":"2026-04-07T01:09:11Z","timestamp":1775524151593,"version":"3.50.1"},"reference-count":50,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2021,8,15]],"date-time":"2021-08-15T00:00:00Z","timestamp":1628985600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2020R1A4A3079595"],"award-info":[{"award-number":["2020R1A4A3079595"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>In the concrete industry, various R&amp;D efforts have been devoted to self-healing technology, which can maintain the long-term performance of concrete structures, which is important in terms of sustainable development. Cracks in cement composites occur and propagate because of various internal and external factors, reducing the composite\u2019s stability. Interest in \u201cself-healing\u201d materials that can repair cracks has led researchers to embed self-healing capsules in cement composites. Overcoming the limitations of polymer capsules produced by chemical manufacturing methods, three-dimensional (3D) printing can produce capsules quickly and accurately and offers advantages such as high material strength, low cost, and the ability to fabricate capsules with complex geometries. We performed structural analysis simulations, experimentally evaluated the mechanical properties and solubility of poly(lactic acid) (PLA) capsules, and examined the effect of the capsule wall thickness and printing direction on cement composites embedded with these capsules. Thicker capsules withstood larger bursting loads, and the capsule rupture characteristics varied with the printing angle. Thus, the capsule design parameters must be optimized for different environments. Although the embedded capsules slightly reduced the compressive strength of the cement composites, the benefit of the encapsulated self-healing agent is expected to overcome this disadvantage.<\/jats:p>","DOI":"10.3390\/ma14164578","type":"journal-article","created":{"date-parts":[[2021,8,15]],"date-time":"2021-08-15T21:43:55Z","timestamp":1629063835000},"page":"4578","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Simulated and Experimental Investigation of the Mechanical Properties and Solubility of 3D-Printed Capsules for Self-Healing Cement Composites"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2142-3745","authenticated-orcid":false,"given":"Se-Jin","family":"Choi","sequence":"first","affiliation":[{"name":"Department of Architectural Engineering, Wonkwang University, 460 Iksan-daero, Iksan 54538, Korea"}]},{"given":"Ji-Hwan","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Architectural Engineering, Wonkwang University, 460 Iksan-daero, Iksan 54538, Korea"}]},{"given":"Hyojin","family":"Jeong","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Wonkwang University, 460 Iksan-daero, Iksan 54538, Korea"}]},{"given":"Ja-Sung","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Electronics Convergence Engineering, Wonkwang University, 460 Iksan-daero, Iksan 54538, Korea"}]},{"given":"Tae-Uk","family":"Lim","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2807-9980","authenticated-orcid":false,"given":"Haye Min","family":"Ko","sequence":"additional","affiliation":[{"name":"Department of Chemistry & Wonkwang, Institute of Material Science and Technology, Wonkwang University, 460 Iksan-daero, Iksan 54538, Korea"}]},{"given":"Sung Hoon","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Electronics Convergence Engineering & Wonkang, Institute of Material Science and Technology, Wonkwang University, 460 Iksan-daero, Iksan 54538, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7060-2010","authenticated-orcid":false,"given":"Wonsuk","family":"Jung","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"669","DOI":"10.1016\/j.conbuildmat.2004.04.027","article-title":"Mechanical properties of high-strength steel fiber-reinforced concrete","volume":"18","author":"Song","year":"2004","journal-title":"Constr. 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