The cell transmission model (CTM), developed by Daganzo in 1994, has not been fully exploited as an operations model for analysis of large-scale traffic networks. Because of its macroscopic / mesoscopic features, CTM offers calibration and computational advantages over microscopic models. This paper demonstrates specific improvements to the original form of CTM to increase its accuracy and realism of traffic flow representation. These improvements include modifications to provide flexibility in selection of cell lengths, non-integer movements of vehicles between cells, and algorithmic enhancements in the merging and diverging logic. The effect of such improvements on the performance of CTM was evaluated independently and comparatively. A sample freeway network of I-10 corridor in Baton Rouge was used to evaluate and compare the performance of the improved version of CTM versus CORSIM under heavily congested traffic conditions. The results showed comparable performance of both platforms in terms of link occupancy (density) and total network travel time.
Samenvatting