Citation

Singh I. Indian Highw. 2005; 33(9): 81-99.

Copyright

(Copyright © 2005, Indian Roads Congress)

DOI

unavailable

PMID

unavailable

Abstract

The paper presents an overview of the traffic assignment process and summarises the practical problems faced by users of traffic-assignment models. The five elements in the application of computerised traffic-assignment are described: network preparation (intersections, interchanges, centroids and connectors), establishing the origin-destination (O-D) demands, identifying a traffic-assignment technique; calibrating and validating the model; and forecasting. The problems associated with traffic assignment include network representation problems (micro-macro network coding, coding of permissible U-turns), coding of operational strategies, the level of details and network aggregation, system-subarea data translation problems, the refinement of computerised traffic-volume forecasts, traffic data for more detailed networks, model calibration problems (base-year O-D Matrix, network representation, assignment techniques, link-performance functions), and forecasting problems (traffic volumes for different forecasting years, checking accuracy of traffic forecasts, site-impact studies).