{"id":{"repo_id":"buffalo","oai_identifier":"oai:ubir.buffalo.edu:10477/86851"},"canonical_url":"https://search.dev.ndltd.org/etd/buffalo/oai:ubir.buffalo.edu:10477/86851","repository":{"repo_id":"buffalo","name":"Buffalo","base_url":"https://ubir.buffalo.edu/oai/request"},"display":{"title":"Effect of Preshaking on Cyclic Resistance of Clean Sand – A Laminar Box Study","abstract":"M.S.","abstract_html":"M.S.","abstract_has_math":false,"creators":["Roy, Rupsa; 0000-0002-1066-0921"],"institution":"State University of New York at Buffalo","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Thevanayagam, Sabanayagam","Civil, Structural and Environmental Engineering"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2025,"date_issued":"2025-02-25T23:23:26Z","date_published":"2025-02-25T23:23:26Z","updated_at":"2026-07-27T19:05:37Z","subjects":["civil engineering"],"languages":["eng"],"rights":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/10477/86851","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Thevanayagam, Sabanayagam","Civil, Structural and Environmental Engineering"]},{"key":"dc:creator","label":"Author","values":["Roy, Rupsa; 0000-0002-1066-0921"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2025-02-25T23:23:26Z","2020","2020-08-10 03:16:25"]},{"key":"dc:publisher","label":"Institution","values":["State University of New York at Buffalo"]},{"key":"dc:type","label":"Dc Type","values":["Text","Thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["civil engineering"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/10477/86851"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["M.S.","Earthquake-induced liquefaction of saturated loose sand deposits is a major cause of damage to the built environment. Strong shaking earthquakes are preceded by mild or weak shakes. They are also followed by mild or weak shakes. The effects of mild shakes on cyclic resistance of sands to resist liquefaction due to future strong shaking remains a question. Recent studies by Dobry et al. (2019), based on a series of large-scale laminar box shake table experiments on 5m deep 'fresh' deposit without any 'aging' effects (Huang 2015), indicate mild shakings tend to strengthen the soil. This thesis reexamines this idea by looking at the same laminar box experimental data. The focus is on the effects of multiple preshakings on the cumulative dissipated energy per unit volume of soil during the shakings to reach a reference liquefaction-threshold shear strain level of 0.01%. This reference strain was chosen in this study as it is known that it's only after this threshold strain level, onset of large pore pressures develops, and liquefaction occurs (Dobry et al. 1982). This study focused on the soil response at mid depth in the laminar box. The shaking experiments (Huang 2015) involved seven repetitive shaking series. Each series consisted of a strong shaking (at 0.15 g peak base acceleration, 15 cycles), followed by 5 successive weak shakings (at 0.03 g peak base acceleration for a short duration), followed by a mild shaking (0.03g peak base acceleration, 15 cycles). This series sequence was repeated seven times on the same soil deposit. It is found that, for medium dense sands, a series of weak shakings following a strong shaking appear to strengthen the soil. The dissipated energy up to the threshold strain (0.01%) increases steadily for each successive weak shaking. The maximum strain reached, and the maximum pore pressure generated during shaking decreases steadily. During subsequent strong shaking, immediately following the weak shakes, a larger amount of energy is dissipated to reach the threshold strain level compared to the energy dissipated in the prior strong shaking event immediately preceding the weak shakes. This tendency repeats for subsequent such sequence of shakings involving multiple weak shakes followed by a strong shaking.","**To request an accessible version of the file(s) associated with this item, contact library@buffalo.edu. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.**"]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Effect of Preshaking on Cyclic Resistance of Clean Sand – A Laminar Box Study"]}]}],"canonical_facts":{"dc:contributor":["Thevanayagam, Sabanayagam","Civil, Structural and Environmental Engineering"],"dc:creator":["Roy, Rupsa; 0000-0002-1066-0921"],"dc:date":["2025-02-25T23:23:26Z","2020","2020-08-10 03:16:25"],"dc:description":["M.S.","Earthquake-induced liquefaction of saturated loose sand deposits is a major cause of damage to the built environment. Strong shaking earthquakes are preceded by mild or weak shakes. They are also followed by mild or weak shakes. The effects of mild shakes on cyclic resistance of sands to resist liquefaction due to future strong shaking remains a question. Recent studies by Dobry et al. (2019), based on a series of large-scale laminar box shake table experiments on 5m deep 'fresh' deposit without any 'aging' effects (Huang 2015), indicate mild shakings tend to strengthen the soil. This thesis reexamines this idea by looking at the same laminar box experimental data. The focus is on the effects of multiple preshakings on the cumulative dissipated energy per unit volume of soil during the shakings to reach a reference liquefaction-threshold shear strain level of 0.01%. This reference strain was chosen in this study as it is known that it's only after this threshold strain level, onset of large pore pressures develops, and liquefaction occurs (Dobry et al. 1982). This study focused on the soil response at mid depth in the laminar box. The shaking experiments (Huang 2015) involved seven repetitive shaking series. Each series consisted of a strong shaking (at 0.15 g peak base acceleration, 15 cycles), followed by 5 successive weak shakings (at 0.03 g peak base acceleration for a short duration), followed by a mild shaking (0.03g peak base acceleration, 15 cycles). This series sequence was repeated seven times on the same soil deposit. It is found that, for medium dense sands, a series of weak shakings following a strong shaking appear to strengthen the soil. The dissipated energy up to the threshold strain (0.01%) increases steadily for each successive weak shaking. The maximum strain reached, and the maximum pore pressure generated during shaking decreases steadily. During subsequent strong shaking, immediately following the weak shakes, a larger amount of energy is dissipated to reach the threshold strain level compared to the energy dissipated in the prior strong shaking event immediately preceding the weak shakes. This tendency repeats for subsequent such sequence of shakings involving multiple weak shakes followed by a strong shaking.","**To request an accessible version of the file(s) associated with this item, contact library@buffalo.edu. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.**"],"dc:format":["application/pdf"],"dc:identifier":["http://hdl.handle.net/10477/86851"],"dc:language":["eng"],"dc:publisher":["State University of New York at Buffalo"],"dc:rights":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."],"dc:subject":["civil engineering"],"dc:title":["Effect of Preshaking on Cyclic Resistance of Clean Sand – A Laminar Box Study"],"dc:type":["Text","Thesis"]},"updated_at":"2026-07-27T19:05:37Z"}