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dc.contributor.advisorJones, Harry L.en_US
dc.creatorSharpe, Graeme Peteren_US
dc.date.accessioned2010-01-15T00:15:38Zen_US
dc.date.accessioned2010-01-16T02:21:12Z
dc.date.available2010-01-15T00:15:38Zen_US
dc.date.available2010-01-16T02:21:12Z
dc.date.created2007-08en_US
dc.date.issued2009-06-02en_US
dc.identifier.urihttp://hdl.handle.net/1969.1/ETD-TAMU-1912
dc.description.abstractMulti-beam bridges made from precast concrete box girders are one of the most common bridge types used in the United States. One problem that affects these bridges is the development of longitudinal or reflective cracks on the road surface because of failure of the shear keys. Some states have attempted to correct this problem by redesigning the shear key or adding post-tensioning, but the problem persists in many new bridges. The purpose of this study is to investigate why these shear key failures are occurring. This project studies two types of box girder designs, the common Precast/Prestressed Concrete Institute (PCI) box girder bridges and the Texas Department of Tranportation (TxDOT) box girder bridge. In the past, reflective cracking has occurred in bridges of both types. The analysis procedure involves finite element analyses of bridge models with realistic support and loading conditions, and comparing the PCI and TxDOT bridges. The results indicate that both PCI and TxDOT box girder have sufficient strength to resist cracking from vehicular loads, but uneven temperature changes and shrinkage strains cause high tensile stresses in the shear key regions and lead to reflective cracking. The analyses showed the highest stresses were often times near the supports, rather than at midspan. Past studies have proposed using larger composite deck slabs, transverse posttensioning, or full-depth shear keys to prevent shear key failure. Composite slabs were the most effective way to reduce high stresses in shear keys, and were effective for all loading cases considered. Post-tensioning and full-depth keys also showed a reduction in shear key stresses, but were less effective.en_US
dc.format.mediumelectronicen_US
dc.format.mimetypeapplication/pdfen_US
dc.language.isoen_USen_US
dc.subjectBox Girdersen_US
dc.subjectShear Keysen_US
dc.subjectThermal Analysisen_US
dc.subjectShrinkageen_US
dc.titleReflective cracking of shear keys in multi-beam bridgesen_US
dc.typeBooken
dc.typeThesisen
thesis.degree.departmentCivil Engineeringen_US
thesis.degree.disciplineCivil Engineeringen_US
thesis.degree.grantorTexas A&M Universityen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelMastersen_US
dc.contributor.committeeMemberHogan, Harryen_US
dc.contributor.committeeMemberJames, Rayen_US
dc.type.genreElectronic Thesisen_US
dc.type.materialtexten_US
dc.format.digitalOriginborn digitalen_US


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