Fragmentation Modes and Crack Evolution of Jointed Rock During Rockfall Impacts: Insights from Parallel DDA Simulations

Fragmentation Modes and Crack Evolution of Jointed Rock During Rockfall Impacts: Insights from Parallel DDA Simulations | 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 Fragmentation Modes and Crack Evolution of Jointed Rock During Rockfall Impacts: Insights from Parallel DDA Simulations Yi-han Wu, Zhi-yuan Zhu, Lu Zheng, Yi Zhou, Dong-po Wang, Gang-qi Chen, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7580914/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 7 You are reading this latest preprint version Abstract Joints are one of the most important factors that influence the fragmentation mode of rocks during impact. Using physical experiments and an OpenMP-based parallel discontinuous deformation analysis (DDA) incorporating virtual joints, this study investigates crack propagation mechanisms and fragmentation modes in rocks with various joint distribution patterns during rockfall impacts. The results indicate that (1) the degree of rock fragmentation can be quantitatively described by the surface area ratio of the equivalent volume sphere ( η ). η increases with increasing joint connectivity rate ( k ), decreases with increasing joint-slope angle ( β ), and tends to increase with increasing joint spacing ( s ). But when k is low, η decreases once s increases to a critical threshold. (2) Rockfall fragmentation modes can divided into three categories according to the destructive morphologies of rocks with different joint distributions. (3) The degree of particle fragmentation within the joint set ( ρ ) quantitatively characterizes the rockfall fragmentation mode. The inherent factor that determines the rockfall fragmentation mode is the length-to-width ratio, b , of the blocks between joints. (4) The three failure modes are internal fragmentation within joint sets ( b 0.2), expansion along outlines of joint sets (0.25 ≤ b ≤ 1 and 0.01 ≤ ρ ≤ 0.2), and expansion along specific joints ( b > 1 and ρ < 0.01). (5) Different joint geometric parameters significantly affect fragment energy and velocities after impact. This study can serve as a reference for particle fragmentation mechanisms in rocks with inherent joints. Rockfall Fragmentation modes Impact Pre-existing joint Discontinuous Deformation Analysis Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviews received at journal 04 May, 2026 Reviewers agreed at journal 02 Apr, 2026 Reviewers agreed at journal 01 Apr, 2026 Reviewers invited by journal 07 Jan, 2026 Editor assigned by journal 13 Dec, 2025 Submission checks completed at journal 11 Sep, 2025 First submitted to journal 10 Sep, 2025 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-7580914","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":571073430,"identity":"54f93a23-6a99-4e7f-bf9d-b549db1ae822","order_by":0,"name":"Yi-han Wu","email":"","orcid":"","institution":"Fujian Agriculture and Forestry University","correspondingAuthor":false,"prefix":"","firstName":"Yi-han","middleName":"","lastName":"Wu","suffix":""},{"id":571073433,"identity":"e9601c5a-faf1-45e7-bde9-cd7f9b55f8a0","order_by":1,"name":"Zhi-yuan Zhu","email":"","orcid":"","institution":"Fuzhou 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Simulations","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"geomechanics-and-geophysics-for-geo-energy-and-geo-resources","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"gggg","sideBox":"Learn more about [Geomechanics and Geophysics for Geo-Energy and Geo-Resources](http://link.springer.com/journal/40948)","snPcode":"40948","submissionUrl":"https://submission.nature.com/new-submission/40948/3","title":"Geomechanics and Geophysics for Geo-Energy and Geo-Resources","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Rockfall, Fragmentation modes, Impact, Pre-existing joint, Discontinuous Deformation Analysis","lastPublishedDoi":"10.21203/rs.3.rs-7580914/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7580914/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eJoints are one of the most important factors that influence the fragmentation mode of rocks during impact. Using physical experiments and an OpenMP-based parallel discontinuous deformation analysis (DDA) incorporating virtual joints, this study investigates crack propagation mechanisms and fragmentation modes in rocks with various joint distribution patterns during rockfall impacts. The results indicate that (1) the degree of rock fragmentation can be quantitatively described by the surface area ratio of the equivalent volume sphere (\u003cem\u003eη\u003c/em\u003e). \u003cem\u003eη\u003c/em\u003e increases with increasing joint connectivity rate (\u003cem\u003ek\u003c/em\u003e), decreases with increasing joint-slope angle (\u003cem\u003eβ\u003c/em\u003e), and tends to increase with increasing joint spacing (\u003cem\u003es\u003c/em\u003e). But when \u003cem\u003ek\u003c/em\u003e is low, \u003cem\u003eη\u003c/em\u003e decreases once \u003cem\u003es\u003c/em\u003e increases to a critical threshold. (2) Rockfall fragmentation modes can divided into three categories according to the destructive morphologies of rocks with different joint distributions. (3) The degree of particle fragmentation within the joint set (\u003cem\u003eρ\u003c/em\u003e) quantitatively characterizes the rockfall fragmentation mode. The inherent factor that determines the rockfall fragmentation mode is the length-to-width ratio, \u003cem\u003eb\u003c/em\u003e, of the blocks between joints. (4) The three failure modes are internal fragmentation within joint sets (\u003cem\u003eb\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.25 and \u003cem\u003eρ\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.2), expansion along outlines of joint sets (0.25\u0026thinsp;\u0026le;\u0026thinsp;\u003cem\u003eb\u003c/em\u003e\u0026thinsp;\u0026le;\u0026thinsp;1 and 0.01\u0026thinsp;\u0026le;\u0026thinsp;\u003cem\u003eρ\u003c/em\u003e\u0026thinsp;\u0026le;\u0026thinsp;0.2), and expansion along specific joints (\u003cem\u003eb\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;1 and \u003cem\u003eρ\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01). (5) Different joint geometric parameters significantly affect fragment energy and velocities after impact. This study can serve as a reference for particle fragmentation mechanisms in rocks with inherent joints.\u003c/p\u003e","manuscriptTitle":"Fragmentation Modes and Crack Evolution of Jointed Rock During Rockfall Impacts: Insights from Parallel DDA Simulations","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-09 11:59:33","doi":"10.21203/rs.3.rs-7580914/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvitedReview","content":"","date":"2026-05-04T22:17:10+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"264591187678857018641556606836209194172","date":"2026-04-02T14:16:12+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"233701945139395921415473671192445087","date":"2026-04-01T17:22:18+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-01-07T19:57:44+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-12-13T21:14:03+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-09-12T01:05:23+00:00","index":"","fulltext":""},{"type":"submitted","content":"Geomechanics and Geophysics for Geo-Energy and Geo-Resources","date":"2025-09-10T08:52:53+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"geomechanics-and-geophysics-for-geo-energy-and-geo-resources","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"gggg","sideBox":"Learn more about [Geomechanics and Geophysics for Geo-Energy and Geo-Resources](http://link.springer.com/journal/40948)","snPcode":"40948","submissionUrl":"https://submission.nature.com/new-submission/40948/3","title":"Geomechanics and Geophysics for Geo-Energy and Geo-Resources","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"3e5a7205-93c9-4666-8abe-eb0dc475b6a8","owner":[],"postedDate":"January 9th, 2026","published":true,"recentEditorialEvents":[{"type":"editorInvitedReview","content":"","date":"2026-05-04T22:17:10+00:00","index":15,"fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-01-09T11:59:33+00:00","versionOfRecord":[],"versionCreatedAt":"2026-01-09 11:59:33","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7580914","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7580914","identity":"rs-7580914","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}