Stabilizing techniques for curved steel I-girders during construction

dc.contributor.advisorHelwig, Todd Aaron, 1965-en
dc.contributor.committeeMemberEngelhardt, Michael D.en
dc.creatorPetruzzi, Brian Jamesen
dc.date.accessioned2010-11-02T20:36:18Zen
dc.date.accessioned2010-11-02T20:36:31Zen
dc.date.accessioned2017-05-11T22:20:35Z
dc.date.available2010-11-02T20:36:18Zen
dc.date.available2010-11-02T20:36:31Zen
dc.date.available2017-05-11T22:20:35Z
dc.date.issued2010-05en
dc.date.submittedMay 2010en
dc.date.updated2010-11-02T20:36:31Zen
dc.descriptiontexten
dc.description.abstractThere are many issues and challenges to deal with when designing a curved I-girder bridge. These challenges primarily deal with the many performance stages that curved I-girder bridges have such as the erection, construction, and in-service stages. When design engineers assess the stability of a bridge system, they typically evaluate the system in its final configuration with all cross frames attached and the hardened concrete deck placed. The evaluation of girder stability during erection and early stages of construction stages is difficult because of the limited presence of bracing in the system. Due to a lack of readily available analytical tools, many contractors do not conduct detailed analytical evaluations of the bridge behavior during early stages of the construction when stability is often critical. Instead, many contractors use rules of thumb and experience to ensure stability during erection. Erection and construction practices typically vary among contractors and consistent erection methods are a rarity. Although some rules of thumb may be quite conservative, others are much less so. Therefore, coming up with design guidelines based on parametric studies rather than rules of thumb are desirable to help allow the contractor and the designer to work together to prevent issues that may occur due to the lack of communication between the two professions. Lastly, many challenges arise due to the complex geometry of curved I-girders. To prevent excessive rotation in erected girders, three points of vertical support are often provided. Two of these points usually consist of permanent supports in the form of bridge piers or abutments. The third point of support may consist of a temporary support in the form of a shore tower or holding crane. Cases where a holding crane may be satisfactory over a shore tower are also not well understood. To improve the understanding of lifting practices and temporary support requirements, parametric studies were conducted using the finite element program ANSYS. Field data consisting of displacement, stress, and girder rotations gathered from two tests were used to validate both the linear and geometric non-linear three-dimensional FEA models. Upon validation, the finite element model was used to conduct linear and geometric non-linear analyses to determine critical factors in curved I-girder bridges during construction. Specifically, serviceability limit states were studied for the lifting of curved girders. For partially constructed states, parametric studies were conducted to determine optimal locations to place temporary supports as well as to investigate stability differences between using a shore tower and a holding crane. Recommendations are presented to provide guidance for the lifting of curved I-girders as well as to maximize stability of partially constructed bridges.en
dc.description.departmentCivil, Architectural, and Environmental Engineeringen
dc.format.mimetypeapplication/pdfen
dc.identifier.urihttp://hdl.handle.net/2152/ETD-UT-2010-05-1364en
dc.language.isoengen
dc.subjectBridgesen
dc.subjectErectionen
dc.subjectConcrete placementen
dc.subjectStabilityen
dc.subjectCurved steel I-girdersen
dc.subjectI-girdersen
dc.subjectConstructionen
dc.subjectBridge constructionen
dc.subjectI-girder bridgesen
dc.subjectLiftingen
dc.subjectPartially constructed bridgesen
dc.subjectDesign and constructionen
dc.titleStabilizing techniques for curved steel I-girders during constructionen
dc.type.genrethesisen

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