Study on the Mechanism of Fracturing and Permeability Enhancement of Coal Body under Liquid Nitrogen Freeze-Thaw Cycles

Study on the Mechanism of Fracturing and Permeability Enhancement of Coal Body under Liquid Nitrogen Freeze-Thaw Cycles | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Study on the Mechanism of Fracturing and Permeability Enhancement of Coal Body under Liquid Nitrogen Freeze-Thaw Cycles Ma Heng, Tang Pengyang, Wang Xiaoqi, Ke Gao This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7571163/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract To investigate the mechanical properties and fracture damage variations of deep coal and rock under liquid nitrogen freeze-thaw cycles, triaxial loading and seepage experiments were conducted on water-saturated freeze-thaw coal and rock. The results show the following:(1) As the number of freeze-thaw cycles increases, cracks gradually expand and form a crack network, leading to a decrease in the compressive strength and elastic modulus of the coal samples.(2) The wave velocity decreases with the increasing number of freeze-thaw cycles, reflecting a reduction in the coal's elastic modulus and integrity.(3) As the number of freeze-thaw cycles increases, the initial permeability, permeability at failure, and overall permeability of the sample increase, with the most significant increase observed after five freeze-thaw cycles.(4) As the number of freeze-thaw cycles increases, the coal becomes fragmented into granular particles, resulting in a denser overall structure. The number of generated pores and fractures increases, thereby enhancing permeability, and the extent of improvement is gradually increasing. Water-saturated coal liquid nitrogen freeze-thaw Non-contact Digital Image Processing Fluid solid interaction rock mechanics Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7571163","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":524558621,"identity":"37a41532-0f19-4419-a2c3-2addea5f7057","order_by":0,"name":"Ma Heng","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Ma","middleName":"","lastName":"Heng","suffix":""},{"id":524558622,"identity":"899c9879-0ee2-4fc1-8a33-987df88c825b","order_by":1,"name":"Tang 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