Experimental simulation investigation on fracture behavior and bolt-anchoring mechanism in a circular tunnel under support in layered rock mass

Experimental simulation investigation on fracture behavior and bolt-anchoring mechanism in a circular tunnel under support in layered rock mass | 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 Article Experimental simulation investigation on fracture behavior and bolt-anchoring mechanism in a circular tunnel under support in layered rock mass Yulong Chen, Duo Xu, Junyang Teng, Kaiyuan Deng, Honghua Song This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9264309/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 9 You are reading this latest preprint version Abstract This paper aims to explore the fracture behavior and bolt-anchoring mechanism in circular tunnel under support in layered rock mass. Seven support methods, horizontal and vertical bedding planes are set up, and cubic rock-like material samples with a prefabricated circular hole and bedding planes are tested under uniaxial compression. During the compression, the failure of the hole sidewall is monitored by a camera. The fracture behavior in tunnels under support in layered rock mass is reproduced. After uniaxial compression failure, the fracture behavior of specimens is analyzed via CT scanning, and the bolt-anchoring mechanism is analyzed. The results demonstrate that the system anchor bolt and steel floral pipe provide higher improvement. The shotcrete and steel arch can provide supporting pressure for the tunnel, which effectively prevents the surrounding rock from spalling damage. The strength increment for the vertical bedding specimen is larger than that for the horizontal bedding specimen. CT observations combined with theoretical analysis indicate that the anchor bolt generates anchoring effect by improving the stress state and the mechanical properties of the surrounding rock in the anchorage zone where the fractures are shrunk, arrested, and swerved, which could increase the bearing capacity of the surrounding rock. Physical sciences/Energy science and technology Physical sciences/Engineering Physical sciences/Materials science Earth and environmental sciences/Solid earth sciences circular tunnel support anchor bolt anchoring mechanism bedding Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 04 May, 2026 Reviews received at journal 21 Apr, 2026 Reviewers agreed at journal 20 Apr, 2026 Reviewers agreed at journal 08 Apr, 2026 Reviewers invited by journal 08 Apr, 2026 Editor invited by journal 06 Apr, 2026 Editor assigned by journal 01 Apr, 2026 Submission checks completed at journal 01 Apr, 2026 First submitted to journal 30 Mar, 2026 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. 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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-9264309","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":619380250,"identity":"d3d0a4bf-34d2-4166-ad92-3b7d6f82c9bd","order_by":0,"name":"Yulong Chen","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAy0lEQVRIiWNgGAWjYBACfvnnBw7/4KmR42dvIFKLZENO4mMGmWPGkj0HiNRi0JBgbMxgw5y44UYCsVoYDqRJF+SwJW64+XjjDYYam2iCWswZG49JzzgjYzzzdlqxBcOxtNwGQlosmxnSJHh72GT7bueYSTA2HCasxeAYg5kE7z9mxoabZ4jVcobB2JiHh1lxwg0eIrVIzuBJfDiDBxTIQL8kEOMXfgn2Awc+gKPy8MYbH2psCGtBcaREAinKIVpI1TEKRsEoGAUjAwAAa+hA/YI8aNIAAAAASUVORK5CYII=","orcid":"","institution":"State Key Laboratory of Water Resource Protection and Utilization in Coal Mining","correspondingAuthor":true,"prefix":"","firstName":"Yulong","middleName":"","lastName":"Chen","suffix":""},{"id":619380251,"identity":"580753f1-5a06-4ed7-85d3-72588589c83d","order_by":1,"name":"Duo Xu","email":"","orcid":"","institution":"State Key Laboratory of Water Resource Protection and Utilization in Coal Mining","correspondingAuthor":false,"prefix":"","firstName":"Duo","middleName":"","lastName":"Xu","suffix":""},{"id":619380258,"identity":"9f29e443-8f72-43d9-8308-d987681a740f","order_by":2,"name":"Junyang Teng","email":"","orcid":"","institution":"Chongqing University","correspondingAuthor":false,"prefix":"","firstName":"Junyang","middleName":"","lastName":"Teng","suffix":""},{"id":619380259,"identity":"45c9f296-857c-448d-af05-f454dbc56134","order_by":3,"name":"Kaiyuan Deng","email":"","orcid":"","institution":"China University of Mining and Technology-Beijing","correspondingAuthor":false,"prefix":"","firstName":"Kaiyuan","middleName":"","lastName":"Deng","suffix":""},{"id":619380262,"identity":"f636c8f3-5d14-414b-9476-a1de9d342c6c","order_by":4,"name":"Honghua Song","email":"","orcid":"","institution":"China University of Mining and Technology-Beijing","correspondingAuthor":false,"prefix":"","firstName":"Honghua","middleName":"","lastName":"Song","suffix":""}],"badges":[],"createdAt":"2026-03-30 08:38:45","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9264309/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9264309/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":106977509,"identity":"4cb9dbee-1ce1-4972-b83b-727f08200acc","added_by":"auto","created_at":"2026-04-15 11:03:45","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2626161,"visible":true,"origin":"","legend":"","description":"","filename":"fracturebehaviorandboltanchoringmechanism07.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9264309/v1_covered_80e16e25-2487-412b-9df9-42b52fbb396c.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Experimental simulation investigation on fracture behavior and bolt-anchoring mechanism in a circular tunnel under support in layered rock mass","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":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"circular tunnel, support, anchor bolt, anchoring mechanism, bedding","lastPublishedDoi":"10.21203/rs.3.rs-9264309/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9264309/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis paper aims to explore the fracture behavior and bolt-anchoring mechanism in circular tunnel under support in layered rock mass. Seven support methods, horizontal and vertical bedding planes are set up, and cubic rock-like material samples with a prefabricated circular hole and bedding planes are tested under uniaxial compression. During the compression, the failure of the hole sidewall is monitored by a camera. The fracture behavior in tunnels under support in layered rock mass is reproduced. After uniaxial compression failure, the fracture behavior of specimens is analyzed via CT scanning, and the bolt-anchoring mechanism is analyzed. The results demonstrate that the system anchor bolt and steel floral pipe provide higher improvement. The shotcrete and steel arch can provide supporting pressure for the tunnel, which effectively prevents the surrounding rock from spalling damage. The strength increment for the vertical bedding specimen is larger than that for the horizontal bedding specimen. CT observations combined with theoretical analysis indicate that the anchor bolt generates anchoring effect by improving the stress state and the mechanical properties of the surrounding rock in the anchorage zone where the fractures are shrunk, arrested, and swerved, which could increase the bearing capacity of the surrounding rock.\u003c/p\u003e","manuscriptTitle":"Experimental simulation investigation on fracture behavior and bolt-anchoring mechanism in a circular tunnel under support in layered rock mass","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-15 11:03:26","doi":"10.21203/rs.3.rs-9264309/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"64342980924246175632439936526726120824","date":"2026-05-05T03:24:21+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-22T00:57:00+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"295794719568556521113929389438414491820","date":"2026-04-20T08:09:17+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"312992554660543522802318761719142674204","date":"2026-04-08T05:58:53+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-04-08T05:52:32+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-04-06T11:59:37+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-04-01T05:28:19+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-04-01T05:27:21+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2026-03-30T08:28:28+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"bdb7d5ed-6a3c-43a0-8647-1b1f42bc9ee0","owner":[],"postedDate":"April 15th, 2026","published":true,"recentEditorialEvents":[{"type":"reviewerAgreed","content":"64342980924246175632439936526726120824","date":"2026-05-05T03:24:21+00:00","index":23,"fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[{"id":65905396,"name":"Physical sciences/Energy science and technology"},{"id":65905397,"name":"Physical sciences/Engineering"},{"id":65905398,"name":"Physical sciences/Materials science"},{"id":65905399,"name":"Earth and environmental sciences/Solid earth sciences"}],"tags":[],"updatedAt":"2026-04-15T11:03:26+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-15 11:03:26","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9264309","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9264309","identity":"rs-9264309","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}