Anisotropic Strength of granular soils in Direct Shear Test by Microstructure Analysis

Anisotropic Strength of granular soils in Direct Shear Test by Microstructure Analysis | 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 Anisotropic Strength of granular soils in Direct Shear Test by Microstructure Analysis Homayoun Shaverdi, Farzin Kalantary This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7331838/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 Granular soils deposited under gravity naturally develop an anisotropic particle arrangement. Variations in loading direction relative to the particle bedding plane intensify the anisotropy of the shear strength. This paper presents a micro-mechanically based anisotropic strength criterion for granular soils under direct shear conditions. The anisotropic resistance, arising from the internal structure of particles relative to the weakest plane or shear band, is captured using physically meaningful and easily measurable parameters. The anisotropic component of shear resistance is shown to depend on the deviation between the bedding plane and the most mobilized plane, referred to as the Spatially Mobilized Plane (SMP). By introducing a frequency distribution function for contact normals, relative to the mobilized plane, a relationship is established between shear resistance,, the inter-particle friction angle, , and anisotropic parameters, based on a microscopic analysis of grain behavior. Two types of anisotropies are considered: one associated with contact normal, and the other with the orientation of particles long axes. Differences in shear resistance are attributed to both the degree of anisotropy, and the angle of deposition relative to the SMP. All parameters in the proposed criterion can be readily determined through laboratory testing. The validity of the formulation is confirmed through experimental results on four different types of sands. Anisotropy Internal friction angle Fabric Failure criterion Contact normals 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. 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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-7331838","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":505669958,"identity":"c64ec0fc-63ad-45cc-8d5b-6c98ede3b3dd","order_by":0,"name":"Homayoun Shaverdi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABBklEQVRIiWNgGAWjYBACAwSTB0wytrE3MDCTqIXnAKlaGiQS8GsxZ+9O/MxTcTiPgf/sQSDjnmyf5BvDzwUVNgz87d0J2LRY9pzdLM1z5nAxg0ReMpBRbNwmnWMsPeNMGoPEmbMbsDrsRu4Gad62w4kNEjwGkjPbEhKBWgxAIgwGErm4tGz+DdbCf8b458x/QC2SZ4x/E9CyDWILQ46ZxMcGoBYJHjP8tpw5u81yzpl0oMNyzCw+HEswbuNJK7PmOZPGg9Mvx3s333hTYQ122I2EmgTZ+e2HN9/mqbCR42/vxaoFBJhAMWJ/AM7nAEcWDy7lIMD4A5XP/gCf6lEwCkbBKBh5AAA33WLsIzG2EQAAAABJRU5ErkJggg==","orcid":"","institution":"Ilam University","correspondingAuthor":true,"prefix":"","firstName":"Homayoun","middleName":"","lastName":"Shaverdi","suffix":""},{"id":505669959,"identity":"58a97519-c5e2-44ac-86eb-c904ef919218","order_by":1,"name":"Farzin Kalantary","email":"","orcid":"","institution":"Khaje Nasir Toosi University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Farzin","middleName":"","lastName":"Kalantary","suffix":""}],"badges":[],"createdAt":"2025-08-09 06:53:13","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7331838/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7331838/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":94988310,"identity":"3e4849e7-1eab-4d04-9403-e67ea831ccff","added_by":"auto","created_at":"2025-11-03 07:08:34","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1659962,"visible":true,"origin":"","legend":"","description":"","filename":"Manuscript.V222.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7331838/v1_covered_7b499aea-b493-4b82-ad48-31997a175b7c.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Anisotropic Strength of granular soils in Direct Shear Test by Microstructure Analysis","fulltext":[],"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":true,"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":"Anisotropy, Internal friction angle, Fabric, Failure criterion, Contact normals","lastPublishedDoi":"10.21203/rs.3.rs-7331838/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7331838/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Granular soils deposited under gravity naturally develop an anisotropic particle arrangement. 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