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dc.contributor.authorHardyniec, Andrew B.en_US
dc.date.accessioned2014-03-14T20:44:20Z
dc.date.available2014-03-14T20:44:20Z
dc.date.issued2009-08-20en_US
dc.identifier.otheretd-08272009-103422en_US
dc.identifier.urihttp://hdl.handle.net/10919/34806
dc.description.abstractCreated in response to the aging infrastructure in the United States, the Long Term Bridge Performance Program (LTBPP) under the Federal Highway Administration (FHWA) proposes to assess the long-term performance of representative bridges through nondestructive evaluation (NDE) techniques and visual inspection. For consistency, a set of guidelines is needed to define the procedures for testing each bridge. The NDE techniques involve dynamic testing, and the protocol for this testing has yet to be finalized. To evaluate the dynamic testing guidelines, a 103 ft single-span, simply supported highway bridge was dynamically tested. The test bridge was characterized by a skew of 34° and superelevation around 4%. Forced vibration testing involved an impact hammer with accelerometers measuring the response. Resonant frequencies were identified from the data by picking peaks from the magnitudes of the frequency response functions (FRF). Eleven modes were identified with frequencies ranging from 2.75 Hz to 22.5 Hz. Mode shapes associated with each mode were constructed using the imaginary components of the FRFs. The half-power bandwidth method was used to estimate the damping for each mode, with values ranging from 1% to 5% of critical damping. Finite element (FE) models of the bridge were constructed in the commercial FE software Abaqus. The effects of adding and removing superelevation and skew, varying mesh refinement, and changing boundary conditions on modal parameters were thoroughly investigated. FE models were compared to the experimental results by directly comparing frequencies and using the modal assurance criterion to compare mode shapes. Support conditions of the actual structure were bounded using the results of the comparison. Much insight was gained about forced vibration testing as applied to a full-scale bridge. The spectral resolution of the data proved to limit the accuracy and confidence of detecting closely-spaced modes and calculating damping estimates. Also, a more controlled method of exciting the structure was desired, such as using a shaker with a known input. Resonant frequencies of the FE models were sensitive to changes in boundary conditions, with some frequencies doubling. Both changes in boundary conditions and including skew and superelevation noticeably affected the mode shapes. When compared to the experimental results, the models with idealized roller and pin boundary conditions provided the best correlations based on resonant frequencies and mode shapes.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartHardyniec_AB_Thesis_2009.pdfen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectFinite Element Methoden_US
dc.subjectModalen_US
dc.subjectDynamicen_US
dc.subjectBridgeen_US
dc.subjectField Testingen_US
dc.titleDynamic Testing and Modeling of a Superelevated Skewed Highway Bridgeen_US
dc.typeThesisen_US
dc.contributor.departmentCivil Engineeringen_US
dc.description.degreeMaster of Scienceen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineCivil Engineeringen_US
dc.contributor.committeechairSotelino, Elisa D.en_US
dc.contributor.committeememberRoberts-Wollmann, Carin L.en_US
dc.contributor.committeememberCousins, Thomas E.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-08272009-103422/en_US
dc.date.sdate2009-08-27en_US
dc.date.rdate2009-09-15
dc.date.adate2009-09-15en_US


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