{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T18:24:38Z","timestamp":1787163878772,"version":"build-2736575974"},"reference-count":28,"publisher":"Public Library of Science (PLoS)","issue":"8","license":[{"start":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T00:00:00Z","timestamp":1787097600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key Research and Development Program of China","award":["2023YFF0615402"],"award-info":[{"award-number":["2023YFF0615402"]}]},{"name":"Tianjin Key Research and Development Program Project","award":["25YFYFFG00240"],"award-info":[{"award-number":["25YFYFFG00240"]}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>Aiming at the common problem of borehole instability caused by mineral hydration in water-sensitive mudstone formations during petroleum drilling, this paper conducts a multi-scale study by integrating X-ray diffraction, triaxial mechanical experiments, and molecular dynamics simulation methods. It systematically analyzes the mineral composition of mudstone, the evolution law of its mechanical properties after hydration, and the microscopic mechanism of hydration. The results indicate that: \u2460 The montmorillonite content in the mudstone dominates its strong water sensitivity, leading to a sharp deterioration in mechanical properties after immersion, with compressive strength decreasing by over 55%; \u2461 Molecular dynamics simulation reveals that montmorillonite hydration is a staged process: water molecules intrude into the interlayer to sequentially form single-layer, double-layer, and triple-layer water film structures, with the interlayer spacing expanding nonlinearly. Na\u207a migrates accordingly and distributes alternately with water molecules. The diffusion coefficient of water molecules is significantly higher than that of Na\u2009\u207a\u2009. These factors collectively cause a continuous decline in interlayer structural stability; \u2462 This microscopic process, from \u201cstaged formation of water films\u201d to \u201cgradual structural destabilization,\u201d directly explains the macroscopic phenomenon of cores exhibiting progressive failure characterized by \u201cinitial spalling followed by fragmentation\u201d with increasing immersion time. This study establishes a complete evolution path of mudstone hydration damage from the atomic scale to the core scale, providing a key theoretical basis for controlling borehole stability by inhibiting interlayer hydration of montmorillonite.<\/jats:p>","DOI":"10.1371\/journal.pone.0356473","type":"journal-article","created":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T17:30:07Z","timestamp":1787160607000},"page":"e0356473","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Molecular dynamics simulation study on macroscopic mechanical deterioration and microscopic hydration mechanism of mudstone"],"prefix":"10.1371","volume":"21","author":[{"given":"Lidong","family":"Hou","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shaojie","family":"Li","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-2057-5539","authenticated-orcid":true,"given":"Jinsong","family":"Bai","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Changhao","family":"Wang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yunzhao","family":"Liu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ziyang","family":"Zhu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,8,19]]},"reference":[{"key":"pone.0356473.ref001","doi-asserted-by":"crossref","first-page":"141065","DOI":"10.1016\/j.energy.2026.141065","article-title":"Integrated modeling and economic assessment of hydrogen storage with wellbore-reservoir-thermo-hydro-mechanical-diffusion coupling","volume":"353","author":"X Gao","year":"2026","journal-title":"Energy"},{"issue":"1","key":"pone.0356473.ref002","doi-asserted-by":"crossref","first-page":"35268","DOI":"10.1038\/s41598-025-17588-9","article-title":"Enhancing wellbore stability through machine learning for sustainable hydrocarbon exploitation","volume":"15","author":"M Mahetaji","year":"2025","journal-title":"Sci Rep"},{"key":"pone.0356473.ref003","doi-asserted-by":"crossref","first-page":"65","DOI":"10.1007\/s44444-025-00066-y","article-title":"Impact of long-term depletion on horizontal wellbore stability in tight reservoirs-including changes in petrophysical and geomechanical properties","volume":"37","author":"NJ Al-Ameri","year":"2025","journal-title":"J King Saud Univ - Eng Sci"},{"issue":"4","key":"pone.0356473.ref004","doi-asserted-by":"crossref","first-page":"5365","DOI":"10.1007\/s00603-025-05049-8","article-title":"Numerical and Experimental Investigation on the Wellbore Stability for Horizontal Drilling in Deep Coal Seams with Partings","volume":"59","author":"Q Yang","year":"2025","journal-title":"Rock Mech Rock Eng"},{"key":"pone.0356473.ref005","doi-asserted-by":"crossref","first-page":"108624","DOI":"10.1016\/j.rineng.2025.108624","article-title":"Regression equation analysis of dynamic and static elastic modulus and Poison\u2019s ratio of Paleogene sandstone reservoirs in Zhanhua sub-sag, Bohai Bay Basin","volume":"29","author":"M Guo","year":"2026","journal-title":"Results Eng"},{"key":"pone.0356473.ref006","doi-asserted-by":"crossref","first-page":"48","DOI":"10.1007\/s10706-025-03569-2","article-title":"Wellbore instability in layered shale under three-dimensional in situ stresses: influence of elastic, hydraulic, and thermal anisotropy","volume":"44","author":"W Liu","year":"2026","journal-title":"Geotech Geol Eng"},{"issue":"11","key":"pone.0356473.ref007","doi-asserted-by":"crossref","first-page":"3389","DOI":"10.3390\/pr13113389","article-title":"Wellbore Stability in Interbedded Weak Formations Utilizing a Shear-Based Method: Numerical Realization and Analysis","volume":"13","author":"Y Han","year":"2025","journal-title":"Processes"},{"issue":"1","key":"pone.0356473.ref008","doi-asserted-by":"crossref","first-page":"42845","DOI":"10.1038\/s41598-025-23872-5","article-title":"Wellbore stability model for argillaceous limestone - claystone thin interbeds under synergistic effect of fluctuating pressure -hydration","volume":"15","author":"K Lv","year":"2025","journal-title":"Sci Rep"},{"key":"pone.0356473.ref009","doi-asserted-by":"crossref","first-page":"130951","DOI":"10.1016\/j.energy.2024.130951","article-title":"System and multi-physics coupling model of liquid-CO2 injection on CO2 storage with enhanced gas recovery (CSEGR) framework","volume":"294","author":"X Gao","year":"2024","journal-title":"Energy"},{"key":"pone.0356473.ref010","unstructured":"Zhu ZY. 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