Crack propagation characteristics and mechanism of energy evolution in intermittent externally fissured sandstone

Crack propagation characteristics and mechanism of energy evolution in intermittent externally fissured sandstone | 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 Crack propagation characteristics and mechanism of energy evolution in intermittent externally fissured sandstone Hui Yu, Shaowei Liu, Housheng Jia, Huaichang Zheng, Zhihe Liu This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-29394/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 Geostress environment and fracture distribution both exert important influences on the mechanical properties and failure modes of fissured rock masses. Laboratory test results are presented here to simulate particle flow code (PFC) in externally double-fissured sandstone samples. Mechanical responses of confining pressure and rock bridge angle on stress-strain curves as well as macroscopic damage and fracture propagation in these samples were studied in order to elucidate energy dissipation mechanisms. The results of this analysis show that fissured sandstone peak strength and elastic modulus as well as peak axial and lateral strain increase significantly as rock bridge angle decreases while peak strength increases slightly in concert with confining pressure. Rock bridge angle exerts an important influence on macro fracturing patterns; when β = 0°, wing cracks from two pre-existing external fissures propagate in opposite directions, but when β = 60°, the inner tips of two external fissures become directly connected. The evolution of specimen fracturing passes through four main stages, elastic compression deformation, stable crack development, unstable crack development, and post-peak accelerated crack development. Internal contact forces reach maximum values at the peak stress point, while cracks are mainly tensile and shear examples are mostly distributed at orientations between 80° and 100°. Shear cracks are mainly generated along the direction of main stress, σ 1 , while pre-peak dissipated energy is small, and increases rapidly at the post-peak. As rock bridge angle decreases, peak strain and boundary energies both increase significantly. Data show that energy and rock bridge angle are approximately linearly positively correlated. Energy Engineering Externally fissured sandstone Rock bridge angle Confining pressure Energy Particle flow code Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Full Text Tables Table 1 Mesoscopic parameters of PFC numerical simulation Parameter Value Parameter Value Particle minimum radius (mm) 0.3 Linear contact modulus (GPa) 7.5 Particle size ratio 1.67 Tangential bond strength (MPa) 56.5 Density (g/cm 3 ) 2.6 Normal bond strength (MPa) 67.8 Parallel bond modulus (GPa) 14.6 Particle stiffness ratio 2.1 Table 2 Peak strength and deformation parameters when σ 3 =10MPa β (°) σ 1 (MPa) ε 1 (10 -3 ) ε 3 (10 -3 ) ε v (10 -3 ) E 0 74.2 4.99 1.16 3.82 14.9 30 62.2 4.26 0.977 3.27 14.2 45 50.8 3.97 0.939 2.49 13.6 60 44.3 3.34 0.846 2.48 13.2 90 30.1 1.58 0.415 1.14 12.5 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-29394","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research","associatedPublications":[],"authors":[{"id":582441,"identity":"8739e0eb-7a49-48f3-b86d-182a8f56ce6b","order_by":1,"name":"Hui Yu","email":"","orcid":"","institution":"Shandong University of Technology","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Hui","middleName":"","lastName":"Yu","suffix":""},{"id":582442,"identity":"c6ff1278-c3ad-4339-bdde-6a3b21c8caad","order_by":2,"name":"Shaowei Liu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAqElEQVRIiWNgGAWjYBACPhDxoMCGh5+9gUgtbCAiwSBNRrLnAGlaDtsY3HAgVgv/GTOJBIPzPAw3GBg/fMwhRotEjrFBgsFtHsbZDcySM7cRpYV34wOQFmaZA2zMvERp4T+74UCCwTkeNokEYrUw5IJsOcDDQ7wWifzPQL8k80jwHGwmzi/8/MfSJD5U2NnbH28++OEjMVqQAGMDaepHwSgYBaNgFOAGANKuLv4XGm8JAAAAAElFTkSuQmCC","orcid":"","institution":"","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Shaowei","middleName":"","lastName":"Liu","suffix":""},{"id":582443,"identity":"2a63cadc-998f-45c8-8358-614b86f700ef","order_by":3,"name":"Housheng Jia","email":"","orcid":"","institution":"Henan Polytechnic University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Housheng","middleName":"","lastName":"Jia","suffix":""},{"id":582444,"identity":"426889f0-5e00-4e70-88d3-d0bd4dce5b0d","order_by":4,"name":"Huaichang Zheng","email":"","orcid":"","institution":"Shandong University of Technology","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Huaichang","middleName":"","lastName":"Zheng","suffix":""},{"id":582445,"identity":"e5637cc6-883b-436f-92b6-8edac880abb0","order_by":5,"name":"Zhihe Liu","email":"","orcid":"","institution":"Shandong University of Technology","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Zhihe","middleName":"","lastName":"Liu","suffix":""}],"badges":[],"createdAt":"2020-05-15 14:34:10","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-29394/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-29394/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":1137602,"identity":"0013abd6-e506-4f53-b389-9a1e49ee47a3","added_by":"auto","created_at":"2020-05-20 14:54:41","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":21084,"visible":true,"origin":"","legend":"Fissured 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PDF\u003c/a\u003e.\u003c/p\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable\u003c/strong\u003e \u003cstrong\u003e1\u003c/strong\u003e Mesoscopic parameters of PFC numerical simulation\u003c/p\u003e\n\u003ctable width=\"408\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd width=\"152\"\u003e\n\u003cp\u003eParameter\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"52\"\u003e\n\u003cp\u003eValue\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"152\"\u003e\n\u003cp\u003eParameter\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"52\"\u003e\n\u003cp\u003eValue\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"152\"\u003e\n\u003cp\u003eParticle minimum radius (mm)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"52\"\u003e\n\u003cp\u003e0.3\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"152\"\u003e\n\u003cp\u003eLinear contact modulus (GPa)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"52\"\u003e\n\u003cp\u003e7.5\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"152\"\u003e\n\u003cp\u003eParticle size ratio\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"52\"\u003e\n\u003cp\u003e1.67\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"152\"\u003e\n\u003cp\u003eTangential bond strength (MPa)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"52\"\u003e\n\u003cp\u003e56.5\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"152\"\u003e\n\u003cp\u003eDensity (g/cm\u003csup\u003e3\u003c/sup\u003e)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"52\"\u003e\n\u003cp\u003e2.6\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"152\"\u003e\n\u003cp\u003eNormal bond strength (MPa)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"52\"\u003e\n\u003cp\u003e67.8\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"152\"\u003e\n\u003cp\u003eParallel bond modulus (GPa)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"52\"\u003e\n\u003cp\u003e14.6\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"152\"\u003e\n\u003cp\u003eParticle stiffness ratio\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"52\"\u003e\n\u003cp\u003e2.1\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2\u003c/strong\u003e Peak strength and deformation parameters when \u003cem\u003e\u0026sigma;\u003c/em\u003e\u003csub\u003e3\u003c/sub\u003e=10MPa\u003c/p\u003e\n\u003ctable width=\"322\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u003cem\u003e\u0026beta; \u003c/em\u003e(\u0026deg;)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"70\"\u003e\n\u003cp\u003e\u003cem\u003e\u0026sigma;\u003c/em\u003e\u003csub\u003e1 \u003c/sub\u003e(MPa)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd 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width=\"50\"\u003e\n\u003cp\u003e12.5\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Externally fissured sandstone, Rock bridge angle, Confining pressure, Energy, Particle flow code","lastPublishedDoi":"10.21203/rs.3.rs-29394/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-29394/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Geostress environment and fracture distribution both exert important influences on the mechanical properties and failure modes of fissured rock masses. Laboratory test results are presented here to simulate particle flow code (PFC) in externally double-fissured sandstone samples. Mechanical responses of confining pressure and rock bridge angle on stress-strain curves as well as macroscopic damage and fracture propagation in these samples were studied in order to elucidate energy dissipation mechanisms. The results of this analysis show that fissured sandstone peak strength and elastic modulus as well as peak axial and lateral strain increase significantly as rock bridge angle decreases while peak strength increases slightly in concert with confining pressure. Rock bridge angle exerts an important influence on macro fracturing patterns; when β = 0°, wing cracks from two pre-existing external fissures propagate in opposite directions, but when β = 60°, the inner tips of two external fissures become directly connected. The evolution of specimen fracturing passes through four main stages, elastic compression deformation, stable crack development, unstable crack development, and post-peak accelerated crack development. Internal contact forces reach maximum values at the peak stress point, while cracks are mainly tensile and shear examples are mostly distributed at orientations between 80° and 100°. Shear cracks are mainly generated along the direction of main stress, σ 1 , while pre-peak dissipated energy is small, and increases rapidly at the post-peak. As rock bridge angle decreases, peak strain and boundary energies both increase significantly. Data show that energy and rock bridge angle are approximately linearly positively correlated.","manuscriptTitle":"Crack propagation characteristics and mechanism of energy evolution in intermittent externally fissured sandstone","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2020-05-20 14:54:37","doi":"10.21203/rs.3.rs-29394/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"58c152d9-001a-4d04-960b-514712878819","owner":[],"postedDate":"May 20th, 2020","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":103566,"name":"Energy Engineering"}],"tags":[],"updatedAt":"2020-05-29T02:59:45+00:00","versionOfRecord":[],"versionCreatedAt":"2020-05-20 14:54:37","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-29394","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-29394","identity":"rs-29394","version":["v1"]},"buildId":"7rjqhiLT3MXkJMwkYKINL","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}