This report summarizes an analytical investigation carried out to develop a set of guidelines for regulation of overload vehicles in Indiana. A formula based first phase evaluation of overload permit requests is developed through statistical study of the rating of a representative sample of the highway bridges in Indiana using a representative sample of overload vehicles observed in the state in 1990 and 1991 plus the HS 20 design vehicle and the two Indiana Toll Road loadings. A sample of 148 bridges is chosen from a total population of 3700 Indiana highway bridges using a proportionate stratified random sampling process. A sample of 25 trucks, with the truck parameters uniformly distributed over their ranges is compiled from the 1990 and 1991 truck population (permit vehicles obtained from INDOT and AASHTO HS Design Vehicle). The selected trucks are used to rate bridges in the selected sample using the Bridge Analysis and Rating System (BARS) program at the operating stress level. BARS is based on elastic line girder and truss analysis. The allowable load, W, is subjected to linear regression analysis with several bridge and truck parameters as regressor or independent variables.

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bridges, rating, permits, overloads, HPR-2042

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Performing Organization

Joint Highway Research Project

Publisher Place

West Lafayette, IN

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