Article ID: | iaor2005305 |
Country: | United States |
Volume: | 37 |
Issue: | 1 |
Start Page Number: | 83 |
End Page Number: | 96 |
Publication Date: | Feb 2003 |
Journal: | Transportation Science |
Authors: | Carey M., Ge Y.E., McCartney M. |
In network models for dynamic traffic assignment the link travel times are often described by “whole-link” models. In particular, they have been expressed as a function of the number of vehicles currently on the link. Such whole-link models are useful approximations and make the network model tractable when flows and travel times are varying over time. Here we propose an alternative whole-link model to approximate travel times. For a vehicle entering a link at time t, we let the link travel time be a function of a weighted average of the inflow rate at the time it enters and the outflow rate at the time it exits. We show that this model ensures first-in-first-out and has other desirable properties. We indicate computational methods for solving the model, apply it to various patterns of inflows, and compare the numerical results with two alternative whole-link models.