{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T21:03:03Z","timestamp":1770843783125,"version":"3.50.1"},"reference-count":38,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2025,6,30]],"date-time":"2025-06-30T00:00:00Z","timestamp":1751241600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>To ensure the green, safe, and efficient extraction of mineral resources and promote sustainability, the stability of mined-out areas has become a critical factor affecting safe production and ecological restoration in underground metal mines. The instability of underground goafs poses a significant threat to mine safety, especially when irregular excavation patterns interact with high ground stress, exacerbating instability risks. Most existing studies lack a systematic and multidisciplinary integrated framework for comprehensive evaluation and management. This paper proposes a trinity research system of \u201cassessment\u2013optimization\u2013governance\u201d, integrating theoretical analysis, three-dimensional fluid\u2013solid coupling numerical simulation, and a filling sequence optimization method based on genetic algorithms. An analysis of data measured from 243 pillars and 49 goafs indicates that approximately 20\u201330% of the pillars have a factor of safety (FoS) below 1.0, signaling immediate instability risks; additionally, 58% do not meet the threshold for long-term stability (FoS \u2265 1.5). Statistical and spatial analyses highlight that pillar width-to-height ratio (W\/H) and cross-sectional area significantly influence stability; when W\/H exceeds 1.5, FoS typically surpasses 2.0. Numerical simulations reveal pore water pressures of 1.4\u20131.8 MPa in deeper goafs, substantially reducing effective stress and accelerating plastic zone expansion. Stability classification categorizes the 49 goafs into 7 \u201cpoor\u201d, 37 \u201cmoderate\u201d, and 5 \u201cgood\u201d zones. A genetic algorithm-optimized filling sequence prioritizes high-risk area remediation, reducing maximum principal stress by 60.96% and pore pressure by 28.6%. Cemented waste rock filling applied in high-risk areas, complemented by general waste rock filling in moderate-risk areas, significantly enhances overall stability. This integrated method provides a scientific foundation for stability assessment and dynamic remediation planning under complex hydrogeological conditions, offering a risk-informed and scenario-specific application of existing tools that improves engineering applicability.<\/jats:p>","DOI":"10.3390\/sym17071024","type":"journal-article","created":{"date-parts":[[2025,6,30]],"date-time":"2025-06-30T03:54:28Z","timestamp":1751255668000},"page":"1024","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Multi-Factor Analysis and Graded Remediation Strategy for Goaf Stability in Underground Metal Mines: Fluid\u2013Solid Coupling Simulation and Genetic Algorithm-Based Optimization Approach"],"prefix":"10.3390","volume":"17","author":[{"given":"Xuzhao","family":"Yuan","sequence":"first","affiliation":[{"name":"School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China"},{"name":"Key Laboratory of Minerals Engineering, Guangxi Higher School, Nanning 530004, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6570-176X","authenticated-orcid":false,"given":"Xiaoquan","family":"Li","sequence":"additional","affiliation":[{"name":"School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China"},{"name":"Key Laboratory of Minerals Engineering, Guangxi Higher School, Nanning 530004, China"}]},{"given":"Xuefeng","family":"Li","sequence":"additional","affiliation":[{"name":"School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China"},{"name":"Key Laboratory of Minerals Engineering, Guangxi Higher School, Nanning 530004, China"}]},{"given":"Tianlong","family":"Su","sequence":"additional","affiliation":[{"name":"School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China"},{"name":"Key Laboratory of Minerals Engineering, Guangxi Higher School, Nanning 530004, China"}]},{"given":"Han","family":"Du","sequence":"additional","affiliation":[{"name":"School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China"},{"name":"Key Laboratory of Minerals Engineering, Guangxi Higher School, Nanning 530004, China"}]},{"given":"Danhua","family":"Zhu","sequence":"additional","affiliation":[{"name":"Archives, Guangxi Minzu University, Nanning 530006, China"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1016\/S1674-4799(09)60003-0","article-title":"Comprehensive Assessment on Dynamic Roof Instability under Fractured Rock Mass Conditions in the Excavation Disturbed Zone","volume":"16","author":"Lai","year":"2009","journal-title":"Int. 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