Elastic analyses, using the finite element method, were done on 108single span skew slab-and-girder bridges. Each structure had 5 girders andstiffnesses were representative of bridges with pretensioned I-girders orsteel I-beams. Spans ranged from 40 to 80 ft, girder spacings from 6 to 9ft, and the skew angle from zero to 60 degrees. The loadings were multiplepoint loads representing two HS20 AASHTO vehicles, and the loads werepositioned to produce maximum bending moments in the girders. Convergencestudies to evaluate the precision of the finite element models were alsodone, and comparisons were made with the results of other studies.An extensive parametric study was done to determine the most importantvariables and to gain an understanding of the response of the skew bridge.Expressions for the design moments in interior and exterior girders werethen developed. These take into account the span and spacing of girders,the stiffness of the girders relative to the slab stiffness, and the angleof skew. The format is the use of the static moment for a girder, withmodifications to this moment based on girder span and spacing, slab togirder stiffness ratio, and skew angle. A similar study was done to obtainfactors for the calculation of deflections, starting with the deflection ofa simple beam.
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