{"id":{"repo_id":"cape-town","oai_identifier":"oai:open.uct.ac.za:11427/5459"},"canonical_url":"https://search.dev.ndltd.org/etd/cape-town/oai:open.uct.ac.za:11427/5459","repository":{"repo_id":"cape-town","name":"University of Cape Town","base_url":"https://open.uct.ac.za/oai/request"},"display":{"title":"The strain rate dependent mechanical properties and modelling of bovine cortical bone in compression","abstract":"Conventional Hopkinson bar experiments resulted in a specimen strain rate that decreases beyond reaching a maximum value at the rise time. The variation in dynamic strain rate was rectified by shaping the Hopkinson bar input pulse with a reusable, conical striker bar. The hypothesis investigated was that a varying strain rate history could result in the measurement of a smeared response for materials with significant strain rate sensitivity. Results indicate that nonuniform, dynamic strain rates result in irregular stress-strain curves; however the stress-strain responses comprise the same corridor as the constant strain rate responses. Bovine cortical bone exhibits significant strain rate sensitivity, with distinct corridors of quasi-static and dynamic stress-strain response. Fracture occurs at a higher stress for both increasing strain rate and bone density. A microstructural investigation indicated that longitudinal compression of bovine bone leads to the formation of shear bands and that fracture depends on the orientation of the vascular porosity.","abstract_html":"Conventional Hopkinson bar experiments resulted in a specimen strain rate that decreases beyond reaching a maximum value at the rise time. The variation in dynamic strain rate was rectified by shaping the Hopkinson bar input pulse with a reusable, conical striker bar. The hypothesis investigated was that a varying strain rate history could result in the measurement of a smeared response for materials with significant strain rate sensitivity. Results indicate that nonuniform, dynamic strain rates result in irregular stress-strain curves; however the stress-strain responses comprise the same corridor as the constant strain rate responses. Bovine cortical bone exhibits significant strain rate sensitivity, with distinct corridors of quasi-static and dynamic stress-strain response. Fracture occurs at a higher stress for both increasing strain rate and bone density. A microstructural investigation indicated that longitudinal compression of bovine bone leads to the formation of shear bands and that fracture depends on the orientation of the vascular porosity.","abstract_has_math":false,"creators":["Van der Westhuizen, Anriëtte"],"institution":"Department of Mechanical Engineering","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Nurick, Gerald N"],"committee_chairs":[],"committee_members":[],"year":2008,"date_issued":"2008","date_published":"2008","updated_at":"2026-07-22T22:23:10Z","subjects":[],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/11427/5459","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Nurick, Gerald N"]},{"key":"dc:creator","label":"Author","values":["Van der Westhuizen, Anriëtte"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2014-07-31T11:18:06Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2014-07-31T11:18:06Z"]},{"key":"dc:date.issued","label":"Date","values":["2008"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Department of Mechanical Engineering"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Cape Town"]},{"key":"dc:type","label":"Dc Type","values":["Doctoral Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["Doctoral"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["PhD"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/11427/5459"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Includes abstract.","Includes bibliographical references (p. 245-253)."]},{"key":"dc:description.abstract","label":"Abstract","values":["Conventional Hopkinson bar experiments resulted in a specimen strain rate that decreases beyond reaching a maximum value at the rise time. The variation in dynamic strain rate was rectified by shaping the Hopkinson bar input pulse with a reusable, conical striker bar. The hypothesis investigated was that a varying strain rate history could result in the measurement of a smeared response for materials with significant strain rate sensitivity. Results indicate that nonuniform, dynamic strain rates result in irregular stress-strain curves; however the stress-strain responses comprise the same corridor as the constant strain rate responses. Bovine cortical bone exhibits significant strain rate sensitivity, with distinct corridors of quasi-static and dynamic stress-strain response. Fracture occurs at a higher stress for both increasing strain rate and bone density. A microstructural investigation indicated that longitudinal compression of bovine bone leads to the formation of shear bands and that fracture depends on the orientation of the vascular porosity."]},{"key":"dc:title","label":"Title","values":["The strain rate dependent mechanical properties and modelling of bovine cortical bone in compression"]}]}],"canonical_facts":{"dc:contributor.advisor":["Nurick, Gerald N"],"dc:creator":["Van der Westhuizen, Anriëtte"],"dc:date.accessioned":["2014-07-31T11:18:06Z"],"dc:date.available":["2014-07-31T11:18:06Z"],"dc:date.issued":["2008"],"dc:description":["Includes abstract.","Includes bibliographical references (p. 245-253)."],"dc:description.abstract":["Conventional Hopkinson bar experiments resulted in a specimen strain rate that decreases beyond reaching a maximum value at the rise time. The variation in dynamic strain rate was rectified by shaping the Hopkinson bar input pulse with a reusable, conical striker bar. The hypothesis investigated was that a varying strain rate history could result in the measurement of a smeared response for materials with significant strain rate sensitivity. Results indicate that nonuniform, dynamic strain rates result in irregular stress-strain curves; however the stress-strain responses comprise the same corridor as the constant strain rate responses. Bovine cortical bone exhibits significant strain rate sensitivity, with distinct corridors of quasi-static and dynamic stress-strain response. Fracture occurs at a higher stress for both increasing strain rate and bone density. A microstructural investigation indicated that longitudinal compression of bovine bone leads to the formation of shear bands and that fracture depends on the orientation of the vascular porosity."],"dc:identifier.uri":["http://hdl.handle.net/11427/5459"],"dc:language.iso":["eng"],"dc:publisher.department":["Department of Mechanical Engineering"],"dc:publisher.institution":["University of Cape Town"],"dc:title":["The strain rate dependent mechanical properties and modelling of bovine cortical bone in compression"],"dc:type":["Doctoral Thesis"],"dc:type.qualificationlevel":["Doctoral"],"dc:type.qualificationname":["PhD"]},"updated_at":"2026-07-22T22:23:10Z"}