{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T12:15:21Z","timestamp":1785413721351,"version":"3.56.0"},"reference-count":43,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2026,7,20]],"date-time":"2026-07-20T00:00:00Z","timestamp":1784505600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Guizhou Provincial Basic Research Program","award":["Qian Ke He Basic-[2025] Youth 306"],"award-info":[{"award-number":["Qian Ke He Basic-[2025] Youth 306"]}]},{"name":"Guizhou Province Higher Education Institutions Undergraduate Teaching Content and Curriculum System Reform Project in 2025","award":["GZJG2025390"],"award-info":[{"award-number":["GZJG2025390"]}]},{"name":"Foundation Research Project of Kaili University","award":["YTH-TD20253I"],"award-info":[{"award-number":["YTH-TD20253I"]}]},{"name":"Foundation Research Project of Kaili University","award":["YTH-PT202405"],"award-info":[{"award-number":["YTH-PT202405"]}]},{"award":["YTH-TD20253I"],"award-info":[{"award-number":["YTH-TD20253I"]}],"id":[{"id":"https:\/\/ror.org\/02hzqbc55","id-type":"ROR","asserted-by":"publisher"}]},{"award":["YTH-PT202405"],"award-info":[{"award-number":["YTH-PT202405"]}],"id":[{"id":"https:\/\/ror.org\/02hzqbc55","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Kaili University 2024 First-Class Course, \u201cEngineering Ethics\u201d","award":["JK202417"],"award-info":[{"award-number":["JK202417"]}]},{"award":["JK202417"],"award-info":[{"award-number":["JK202417"]}],"id":[{"id":"https:\/\/ror.org\/02hzqbc55","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Guizhou Province 2024 First-Class Course, \u201cEngineering Ethics\u201d","award":["2024JKHH0188"],"award-info":[{"award-number":["2024JKHH0188"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Cemented coal gangue backfill (CCGB) is an important material for the resource utilization of mining solid waste, and its long-term stability is strongly affected by aggregate gradation. In this study, aggregate mass fractal dimension was used to characterize the particle size distribution of coal gangue, and four gradation schemes with different fractal dimensions were designed. Uniaxial compressive strength (UCS) tests, stepwise accelerated creep tests, acoustic emission (AE) monitoring, and scanning electron microscopy (SEM) observations were conducted to investigate strength, creep behavior, crack evolution, and damage mechanisms. The results show that P-wave velocity and UCS exhibit generally non-monotonic variations with fractal dimension, with relatively high values in the intermediate fractal-dimension range. The empirical long-term strengths for D=2.20, 2.41, 2.59, and 2.79 are 6.62, 8.83, 7.34, and 7.07 MPa, respectively. AE results indicate that shear cracking first decreases and then increases with fractal dimension, reaching the lowest proportion of 41.8% at D=2.41. SEM observations show that an intermediate fractal dimension improves skeleton continuity and interfacial integrity, thereby suppressing shear-related damage and delaying creep instability. These findings demonstrate that aggregate mass fractal dimension is an effective structural parameter for linking gradation characteristics, creep resistance, and damage evolution of CCGB.<\/jats:p>","DOI":"10.3390\/ma19143110","type":"journal-article","created":{"date-parts":[[2026,7,20]],"date-time":"2026-07-20T12:00:17Z","timestamp":1784548817000},"page":"3110","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Effect of Aggregate Mass Fractal Dimension on Creep Behavior and Damage Mechanisms of Cemented Coal Gangue Backfill"],"prefix":"10.3390","volume":"19","author":[{"given":"Yongjin","family":"Zhang","sequence":"first","affiliation":[{"name":"School of Architectural Engineering, Kaili University, Kaili 556011, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cheng","family":"Li","sequence":"additional","affiliation":[{"name":"School of Architectural Engineering, Kaili University, Kaili 556011, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kangsheng","family":"Xue","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Earth Engineering, China University of Mining and Technology, Xuzhou 221116, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hui","family":"Yang","sequence":"additional","affiliation":[{"name":"School of Architectural Engineering, Kaili University, Kaili 556011, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhen","family":"Lu","sequence":"additional","affiliation":[{"name":"School of Civil Engineering and Architecture, Guizhou Minzu University, Guiyang 550025, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"58231","DOI":"10.1007\/s11356-024-34895-2","article-title":"Opportunities, challenges and modification methods of coal gangue as a sustainable soil conditioner\u2014A review","volume":"31","author":"Tang","year":"2024","journal-title":"Environ. 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