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dc.contributor.advisorWegner, Leonen_US
dc.contributor.advisorSparling, Bruceen_US
dc.creatorMacLeod, Alison Barbaraen_US
dc.date.accessioned2011-04-12T16:11:04Zen_US
dc.date.accessioned2013-01-04T04:29:03Z
dc.date.available2012-04-15T08:00:00Zen_US
dc.date.available2013-01-04T04:29:03Z
dc.date.created2010-11en_US
dc.date.issued2010-11en_US
dc.date.submittedNovember 2010en_US
dc.identifier.urihttp://hdl.handle.net/10388/etd-04122011-161104en_US
dc.description.abstractThe steel through-truss Traffic Bridge, located in Saskatoon, Saskatchewan is over one hundred years old. The bridge has been subject to ongoing maintenance throughout its service life. However, inspection reports from 2005 and 2006 highlighted the severe deterioration experienced primarily by the steel members immediately above and below the deck surface. These reports prompted the City of Saskatoon (COS) to implement a rehabilitation project that involved the installation of a post-tensioning system to relieve the badly corroded bottom chord members of the axial loads due to the self-weight of the structure, in 2006. Due to the severe deterioration and the structural modifications that the Traffic Bridge has endured, a limited scope structural health monitoring (SHM) system, based on strain measurements, was implemented to reduce some of the uncertainty regarding the active load paths occurring at the deck level. The objectives of the SHM study were to obtain more information regarding the actual load paths and ascertain possible types of structural redundancy, to determine how to best model this type of structure, and to find ways to track ongoing deterioration using instrumentation. The SHM study involved controlled truck loading scenarios to permit measurement of the load paths and provide data to compare the measured results to a finite element (FE) model of the instrumented span. In addition, random loading scenarios were used to capture the vertical dynamic response of the structure in order to further refine the FE model. This study focused on the response of one-half of one interior span. A total of 72 strain gauges were installed. The downstream truss was highly instrumented at ten locations, three members of the upstream truss were instrumented to measure the distribution, and the floor joists in the downstream lane were instrumented to establish possible redundancy paths. Using an FE model in combination with the measured strain data, it was found that redundant load paths only existed at the level of the deck. The bottom chord members experienced non-zero strains once the control vehicle was past the span, possibly indicating some level of redundancy. The members believed to relieve a portion of the bottom chord tensile forces included the car joists, edge joists, and the timber deck. The amount of force transferred from the bottom chord to the deck members was found by FE analysis to be highly related to the lateral stiffness of the floor beams. The FE model was adjusted to match the measured results by modifying various modelling parameters. The most important features of the model were that all deck elements were modelled to be located at the elevation of the bottom chord, that the lateral stiffness of the floor beams was reduced by 50% to best represent the transfer of forces to deck elements, and that the stiffness of bottom chord members was reduced to 80% of their pristine values. In combination with calibrated modification factors applied to the measured values, this FE model is believed to be a useful tool to represent the behaviour of the structure to assist in detecting further damage by modelling the strain differential between members, and components of members.en_US
dc.language.isoen_USen_US
dc.subjectSaskatoonen_US
dc.subjectstructural health monitoringen_US
dc.subjectstrain gaugesen_US
dc.subjectTraffic Bridgeen_US
dc.subjecttrussen_US
dc.subjectsteelen_US
dc.subjectbridgeen_US
dc.subjectinstrumentationen_US
dc.subjectSHMen_US
dc.subjectfinite element modelen_US
dc.titleStructural health monitoring of the Traffic Bridge in Saskatoon using strain gaugesen_US
thesis.degree.departmentCivil and Geological Engineeringen_US
thesis.degree.disciplineCivil and Geological Engineeringen_US
thesis.degree.grantorUniversity of Saskatchewanen_US
thesis.degree.levelMastersen_US
thesis.degree.nameMaster of Science (M.Sc.)en_US
dc.type.materialtexten_US
dc.type.genreThesisen_US
dc.contributor.committeeMemberSparks, Gordonen_US
dc.contributor.committeeMemberAfseth, Jeffen_US
dc.contributor.committeeMemberBoulfiza, Mohameden_US
dc.contributor.committeeMemberFeldman, Lisaen_US


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