Macroscopic traffic flow model validation at congested freeway off-ramp areas

• Comparison of two traffic flow models, namely the CTM and the METANET model.
• The models are calibrated and validated using real traffic data.
• The models aim to reproduce traffic congestion due to a saturated freeway off-ramp.
• The validation results show that both models can reproduce the traffic conditions.
• METANET offers a more accurate representation of the prevailing traffic conditions.

The reported study tests, validates and compares two well-known macroscopic traffic flow models in the special, but quite frequently occurring case, where congestion is created due to saturated freeway off-ramps. In particular, the comparison includes the first-order model CTM (Cell Transmission Model) and the second-order model METANET. In order to enable a reliable and fair comparison, the traffic flow models are first calibrated by use of real traffic data from Attiki Odos freeway in Athens, Greece. The resulting models are validated using various traffic data sets, different than the one used for their calibration; the models are then evaluated and compared with respect to their accuracy in the reproduction of congestion created at freeway off-ramp areas.