{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T05:46:18Z","timestamp":1782366378786,"version":"3.54.5"},"reference-count":37,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T00:00:00Z","timestamp":1781740800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004735","name":"Hunan Provincial Natural Science Foundation of China","doi-asserted-by":"crossref","award":["2026JJ70099"],"award-info":[{"award-number":["2026JJ70099"]}],"id":[{"id":"10.13039\/501100004735","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Young Science and Technology Talent Project","award":["2023RC3150"],"award-info":[{"award-number":["2023RC3150"]}]},{"name":"Major Water Conservancy Science and Technology Project of Hunan Province","award":["XSKJ2025056-12"],"award-info":[{"award-number":["XSKJ2025056-12"]}]},{"name":"Research Project of the First Phase of the Key Embankment Reinforcement Project in the Dongting Lake Area","award":["HNST-FW\/DTH-2024-03\/21"],"award-info":[{"award-number":["HNST-FW\/DTH-2024-03\/21"]}]},{"name":"the Science and Technology Innovation Program of Hunan Province","award":["2025AQ2016"],"award-info":[{"award-number":["2025AQ2016"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>The interlayer pores of 3D-printed concrete (3DPC) significantly weaken its macroscopic mechanical properties. In this study, the phase-field cohesive zone model (PF-CZM) is employed as a numerical tool to systematically investigate the weakening mechanisms and crack evolution behavior associated with pore characteristics, including pore size, morphology, spatial orientation, and arrangement, through single-factor numerical simulations with different pore numbers. The results demonstrate that the degradation induced by a single pore is controlled by its effective projection length in the direction perpendicular to the principal tensile stress, with horizontal flat pores being the most detrimental under the same porosity. In the multi-pore system, the connection angle between pores, rather than their spacing, is the key factor determining structural degradation, and a horizontal collinear arrangement is prone to triggering brittle fracture. Furthermore, locally aggregated small pores can form combined defects, whose strength-weakening effect surpasses that of isolated large pores, thereby triggering crack path competition and leading to asymmetrical structural failure. This study reveals the fracture mechanisms driven by complex pore configurations and provides a reference for strength prediction of 3DPC.<\/jats:p>","DOI":"10.3390\/ma19122637","type":"journal-article","created":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T09:18:43Z","timestamp":1781860723000},"page":"2637","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The Influence of Pore Characteristics on the Mechanical Properties of 3D-Printed Concrete Based on the Phase-Field Method"],"prefix":"10.3390","volume":"19","author":[{"given":"Lei","family":"Luo","sequence":"first","affiliation":[{"name":"Hunan Provincial Water Resource Development & Investment Co., Ltd., Changsha 410128, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yao","family":"Li","sequence":"additional","affiliation":[{"name":"College of Water Resources and Civil Engineering, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9075-2331","authenticated-orcid":false,"given":"Wenbin","family":"Xu","sequence":"additional","affiliation":[{"name":"College of Water Resources and Civil Engineering, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuchi","family":"You","sequence":"additional","affiliation":[{"name":"College of Water Resources and Civil Engineering, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1380-9103","authenticated-orcid":false,"given":"Wenqiang","family":"Xu","sequence":"additional","affiliation":[{"name":"College of Water Resources and Civil Engineering, Hunan Agricultural University, Changsha 410128, China"},{"name":"College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 210098, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Deyong","family":"Hu","sequence":"additional","affiliation":[{"name":"College of Water Resources and Civil Engineering, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1016\/j.cemconres.2018.05.006","article-title":"3D printing using concrete extrusion: A roadmap for research","volume":"112","author":"Buswell","year":"2018","journal-title":"Cem. 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