Characteristics and mechanism of down-flow in front of a cylindrical pier under clear-water local scour

Characteristics and mechanism of down-flow in front of a cylindrical pier under clear-water local scour | 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 Characteristics and mechanism of down-flow in front of a cylindrical pier under clear-water local scour Weizheng Wang, Song Wei, Dayong Zhu, Jun Wang, Haipeng Duan This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3530254/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 Local scour of bridge piers is an important factor affecting the stability of piers and down-flow is one of the flow structures involved in local scouring, which is regarded as one of the important factors. But the characteristics and mechanism of down-flow are not yet clearly understood for lack of characteristic parameters. This paper discussed qualitatively that the pressure stress can represent the effect of down-flow, and the pressure stress was accurately measured by installing sensors on the 3D printing models which perfectly reproduces the scour hole at different times.The down-flow is investigated by analyzing the stress state and the scour hole morphology in the scour hole. The results show that the down-flow has a strong interaction with the horseshoe vortex system, which reduces the pressure stress. From the perspective of the flow structures, the water particles collide and rub with each other, producing an effect similar to energy dissipation, which weakens the impact of the down-flow and reduces the pressure stress on the surface of the riverbed. From the perspective of energy transfer, the horseshoe vortex system needs to absorb the energy carried by down-flow to develop during its formation, reducing the energy brought into sediment by down-flow, and reducing the pressure stress. Moreover, this paper found a relationship between the stress state and the tangent slope. The shear stress is an important factor in maintaining the high tangent slope. When the shear stress decreases, a phenomenon of sediment sliding deeper is found, and the tangent slope decreases rapidly. When the shear stress is stabilized, the tangent slope increases with the increase of the pressure stress, which means that the down-flow can promote the development of scour depth. Physical sciences/Physics/Fluid dynamics Physical sciences/Engineering/Mechanical engineering Local scour Stress state Scour hole morphology Interaction among flow structures 3D printing technology 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-3530254","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":246734564,"identity":"a000cd08-a832-4f17-8093-f4fda538a322","order_by":0,"name":"Weizheng Wang","email":"","orcid":"","institution":"Hefei University of Technology","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Weizheng","middleName":"","lastName":"Wang","suffix":""},{"id":246734565,"identity":"b9855b8c-6646-403f-83fa-4772b2f1e254","order_by":1,"name":"Song Wei","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA10lEQVRIiWNgGAWjYBACgwOMDWAGGzPzgQMffpCihZ+dLfHgzB6itEAZkv08xoc52IjRcry5gfFHxR27DYd5Phxm4GGQ5xc7gF+L2ZmDDcw8Z54lbzjMu+FwgQWD4czZCQS03EhsYGZsO5xsANIyg4chweA2IS33HzYw/gRr4XlwmIeNCC32N4Ahxtt22E6ymYeBOC2WZxJBfjmcwM/MZgAMZAnCfjE4fvwBMMQO27PxH3784cMPG3l+aQJagIAdFOWJDRCOBEHlcGBPvNJRMApGwSgYcQAAL0NLL8IETC0AAAAASUVORK5CYII=","orcid":"","institution":"Hefei University of Technology","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Song","middleName":"","lastName":"Wei","suffix":""},{"id":246734566,"identity":"1fee4cdd-3814-4182-9b7b-a674b37f88aa","order_by":2,"name":"Dayong Zhu","email":"","orcid":"","institution":"Zhejiang University Ningbo Institute of Technology","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Dayong","middleName":"","lastName":"Zhu","suffix":""},{"id":246734567,"identity":"1f9425e1-c57f-4947-b991-49ea50e03187","order_by":3,"name":"Jun Wang","email":"","orcid":"","institution":"Hefei University of Technology","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Jun","middleName":"","lastName":"Wang","suffix":""},{"id":246734568,"identity":"afbfbf99-682a-4a31-9e95-65c1ac6982de","order_by":4,"name":"Haipeng Duan","email":"","orcid":"","institution":"Anhui Transportation Holding Group Co. 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But the characteristics and mechanism of down-flow are not yet clearly understood for lack of characteristic parameters. This paper discussed qualitatively that the pressure stress can represent the effect of down-flow, and the pressure stress was accurately measured by installing sensors on the 3D printing models which perfectly reproduces the scour hole at different times.The down-flow is investigated by analyzing the stress state and the scour hole morphology in the scour hole. The results show that the down-flow has a strong interaction with the horseshoe vortex system, which reduces the pressure stress. From the perspective of the flow structures, the water particles collide and rub with each other, producing an effect similar to energy dissipation, which weakens the impact of the down-flow and reduces the pressure stress on the surface of the riverbed. 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When the shear stress is stabilized, the tangent slope increases with the increase of the pressure stress, which means that the down-flow can promote the development of scour depth.\u003c/p\u003e","manuscriptTitle":"Characteristics and mechanism of down-flow in front of a cylindrical pier under clear-water local scour","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2023-11-09 07:21:52","doi":"10.21203/rs.3.rs-3530254/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":"65746158-804f-436d-a0a1-6ced52257d32","owner":[],"postedDate":"November 9th, 2023","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":26042929,"name":"Physical sciences/Physics/Fluid dynamics"},{"id":26042930,"name":"Physical sciences/Engineering/Mechanical engineering"}],"tags":[],"updatedAt":"2023-12-26T06:59:19+00:00","versionOfRecord":[],"versionCreatedAt":"2023-11-09 07:21:52","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3530254","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3530254","identity":"rs-3530254","version":["v1"]},"buildId":"WrCJVZZCHTDjtuVLN7oU0","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}