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dc.contributor.advisorPortela, Genock
dc.contributor.authorBarajas Valdés, Ulises
dc.date.accessioned2018-12-15T11:41:53Z
dc.date.available2018-12-15T11:41:53Z
dc.date.issued2009
dc.identifier.urihttps://hdl.handle.net/20.500.11801/1621
dc.description.abstractBridge superstructures consisting of prestressed, post-tensioned, and preflex systems are evaluated with load rating methodologies adopted by private and government entities, establishing possible restrictions. Based the importance bestowed in these structures to properly withstand service loads, this study considers the following tasks: i) description of the analysis and load rating methods of prestressed beams based on AASHTO requirements; ii) develops a methodology for the analysis and load rating of preflex beams; and iii) present a parametric study of prestressed and preflex bridges with four different span lengths. The results show that AASHTO distribution factors are conservative in comparison to the values obtained from three-dimensional finite element models. In terms of the comparison between both systems (pre-tensioned and preflex), the preflex systems provide more slender sections (in the order of 62%) than prestressed concrete AASHTO I-type sections. Contrarily, live load deflections in the pre-tensioned systems were smaller (in the order of 8%), but for no case AASHTO limits were exceeded. The load rating values obtained from the methodologies considered in this study show that for both systems, the LRFR philosophy results more critical to determine special conditions.en_US
dc.description.abstractLas superestructuras de puentes con vigas de concreto pre-tensado, pos-tensado y preflexionadas son evaluadas con metodologías de calificación, adoptadas por entidades privadas o gubernamentales que establecen posibles restricciones. Basado en la importancia otorgada a estas estructuras para soportar adecuadamente las cargas de servicio, este estudio considera las siguientes tareas: i) descripción de los métodos de análisis y calificación de vigas pre-tensadas/pos-tensadas basados en el código AASHTO, ii) desarrolla una metodología para análisis y calificación de vigas pre-flexionadas, y iii) un estudio paramétrico entre puentes de hormigón pre-tensado y pre-flexionado con cuatro longitudes diferentes de luces. Los resultados que muestran los factores de distribución de AASHTO son conservadores en comparación con los valores obtenidos de los modelos tridimensionales de elementos finitos. En términos de la comparación entre ambos sistemas (pre-tensado y pre-flexionado), los sistemas pre-flexionados proporcionan secciones mas esbeltas (del orden del 62%) a las secciones pre-tensadas (tipo I) de la AASHTO. Por el contrario, los desplazamientos por carga viva en el sistema pre-tensado son menores (en el orden del 8%), pero en ninguno de los casos superan los límites establecidos por AASHTO. Los valores de calificación obtenidos a partir de las metodologías consideradas en este estudio mostraron que la filosofía LRFR resulta más crítica al determinar condiciones especiales.en_US
dc.description.sponsorshipUS Army Corps of Engineers (Engineering Research and Development Center) and of the Department of Civil Engineering and Surveying.en_US
dc.language.isoenen_US
dc.subjectBridge superstructuresen_US
dc.subject.lcshPost-tensioned prestressed concreteen_US
dc.subject.lcshPrestressed concrete bridgesen_US
dc.subject.lcshPrestressed concrete beamsen_US
dc.titleMethodologies for the analysis and load rating of prestressed and preflex bridge superstructuresen_US
dc.typeProject Reporten_US
dc.rights.licenseAll rights reserveden_US
dc.rights.holder(c) 2009 Ulises Barajas Valdésen_US
dc.contributor.committeeLópez, Ricardo
dc.contributor.committeeSuárez, Luis E.
dc.contributor.representativeSchroder, Eduardo
thesis.degree.levelM.E.en_US
thesis.degree.disciplineCivil Engineeringen_US
dc.contributor.collegeCollege of Engineeringen_US
dc.contributor.departmentDepartment of Civil Engineeringen_US
dc.description.graduationYear2009en_US


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