{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/45985"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/45985","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Behavior of a cracked shaft during passage through a critical speed","abstract":"The detection of cracks in structural components and the evaluation of their sizes without the need of removing them from the machine in which they are placed is very important for preventing failures. The objective of this thesis is to study the effects of cracks on the dynamic behavior of shafts under acceleration or deceleration, in order to find methods or procedures capable of detecting the presence of cracks prior to failure. The equations of motion for a simply supported Bernoulli-Euler shaft are developed following Wauer's formulation. Galerkin's Method is used to obtain five-term approximate solutions. The first two natural frequencies are found for both the uncracked and cracked shaft. A computer program is written to perform the numerical integration of the equations. The shaft is subjected to several constant accelerations and decelerations. Tables and figures showing the results are presented along with discussions and comments related to the different runs made and the results obtained. The effect of the initial position angle of the eccentricity is studied to find the influence of this parameter. The effects of crack position and crack depth on the dynamic behavior of the shaft are also included in this work. Time histories and summary graphs are presented to make easier the interpretation of the results. Final conclusions and future research proposals complete the work done in this thesis.","abstract_html":"The detection of cracks in structural components and the evaluation of their sizes without the need of removing them from the machine in which they are placed is very important for preventing failures. The objective of this thesis is to study the effects of cracks on the dynamic behavior of shafts under acceleration or deceleration, in order to find methods or procedures capable of detecting the presence of cracks prior to failure. The equations of motion for a simply supported Bernoulli-Euler shaft are developed following Wauer's formulation. Galerkin's Method is used to obtain five-term approximate solutions. The first two natural frequencies are found for both the uncracked and cracked shaft. A computer program is written to perform the numerical integration of the equations. The shaft is subjected to several constant accelerations and decelerations. Tables and figures showing the results are presented along with discussions and comments related to the different runs made and the results obtained. The effect of the initial position angle of the eccentricity is studied to find the influence of this parameter. The effects of crack position and crack depth on the dynamic behavior of the shaft are also included in this work. Time histories and summary graphs are presented to make easier the interpretation of the results. Final conclusions and future research proposals complete the work done in this thesis.","abstract_has_math":false,"creators":["Andruet, Raul Horacio"],"institution":"Virginia Tech","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Civil Engineering","degree_department":"Civil Engineering","school":null,"contributors":[],"advisors":[],"committee_chairs":["Plaut, Raymond H."],"committee_members":["Rojiani, Kamal B.","Holzer, Siegfried M."],"year":1991,"date_issued":"1991-08-15","date_published":"1991-08-15","updated_at":"2026-07-22T22:19:33Z","subjects":[],"languages":["en"],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-11242009-020021"],"render_values":[{"text":"etd-11242009-020021","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/10919/45985","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.committeechair","label":"Committee Chair","values":["Plaut, Raymond H."]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["Rojiani, Kamal B.","Holzer, Siegfried M."]},{"key":"dc:contributor.department","label":"Department","values":["Civil Engineering"]},{"key":"dc:creator","label":"Author","values":["Andruet, Raul Horacio"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2014-03-14T21:50:31Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2014-03-14T21:50:31Z","2009-11-24"]},{"key":"dc:date.issued","label":"Date","values":["1991-08-15"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Tech"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.dcmitype","label":"Dc Type Dcmitype","values":["Text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Civil Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-11242009-020021"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/45985"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The detection of cracks in structural components and the evaluation of their sizes without the need of removing them from the machine in which they are placed is very important for preventing failures. The objective of this thesis is to study the effects of cracks on the dynamic behavior of shafts under acceleration or deceleration, in order to find methods or procedures capable of detecting the presence of cracks prior to failure. The equations of motion for a simply supported Bernoulli-Euler shaft are developed following Wauer's formulation. Galerkin's Method is used to obtain five-term approximate solutions. The first two natural frequencies are found for both the uncracked and cracked shaft. A computer program is written to perform the numerical integration of the equations. The shaft is subjected to several constant accelerations and decelerations. Tables and figures showing the results are presented along with discussions and comments related to the different runs made and the results obtained. The effect of the initial position angle of the eccentricity is studied to find the influence of this parameter. The effects of crack position and crack depth on the dynamic behavior of the shaft are also included in this work. Time histories and summary graphs are presented to make easier the interpretation of the results. Final conclusions and future research proposals complete the work done in this thesis."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:format.medium","label":"Dc Format Medium","values":["BTD"]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Behavior of a cracked shaft during passage through a critical speed"]}]}],"canonical_facts":{"dc:contributor.committeechair":["Plaut, Raymond H."],"dc:contributor.committeemember":["Rojiani, Kamal B.","Holzer, Siegfried M."],"dc:contributor.department":["Civil Engineering"],"dc:creator":["Andruet, Raul Horacio"],"dc:date.accessioned":["2014-03-14T21:50:31Z"],"dc:date.available":["2014-03-14T21:50:31Z","2009-11-24"],"dc:date.issued":["1991-08-15"],"dc:description.abstract":["The detection of cracks in structural components and the evaluation of their sizes without the need of removing them from the machine in which they are placed is very important for preventing failures. The objective of this thesis is to study the effects of cracks on the dynamic behavior of shafts under acceleration or deceleration, in order to find methods or procedures capable of detecting the presence of cracks prior to failure. The equations of motion for a simply supported Bernoulli-Euler shaft are developed following Wauer's formulation. Galerkin's Method is used to obtain five-term approximate solutions. The first two natural frequencies are found for both the uncracked and cracked shaft. A computer program is written to perform the numerical integration of the equations. The shaft is subjected to several constant accelerations and decelerations. Tables and figures showing the results are presented along with discussions and comments related to the different runs made and the results obtained. The effect of the initial position angle of the eccentricity is studied to find the influence of this parameter. The effects of crack position and crack depth on the dynamic behavior of the shaft are also included in this work. Time histories and summary graphs are presented to make easier the interpretation of the results. Final conclusions and future research proposals complete the work done in this thesis."],"dc:description.degree":["Master of Science"],"dc:format.medium":["BTD"],"dc:format.mimetype":["application/pdf"],"dc:identifier.other":["etd-11242009-020021"],"dc:identifier.uri":["http://hdl.handle.net/10919/45985"],"dc:language.iso":["en"],"dc:publisher":["Virginia Tech"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:title":["Behavior of a cracked shaft during passage through a critical speed"],"dc:type":["Thesis"],"dc:type.dcmitype":["Text"],"thesis:degree_discipline":["Civil Engineering"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:19:33Z"}