Using data primarily from the 1997 Commodity Flow Survey (CFS) this report develops a series of models for estimating the production and attraction of 41 different SCTG commodity groups for 145 geographic units in the United States; 92 of these are the counties of Indiana. This is followed by the calibration of fully-constrained gravity models for the flow of these commodities. Using modal share data from the CFS the generated traffic is divided between the various modes. This project looked primarily at the highway sector and used digital representations of these networks for traffic assignment purposes. A very detailed Indiana digital road network was merged with a USDOT digital highway planning network. New cost metrics were developed for each modal assignment . Productions and attractions were forecasted and the models and assignments were rerun for 2015 and 2025. A chapter on implementation suggests how the results of the project can be used for planning and policy development. Appendices include productions and attractions for the 145 areas, computer program code for the major software developed, national modal share data by commodity, and distance decay curves for the different commodities

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state transport planning, digital road networks, traffic modeling, commodity flow data, microcomputer methods, rail planning, SPR-2860

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Joint Transportation Research Program

Publisher Place

West Lafayette, IN

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