Freeflow on the A13Traffic study and dynamic modeling

Lieu : France

Client : SAPN

Date : 2021 - 2022

Le projet

As part of an overall review of the A14 and A13 freeways between Paris and Caen, SAPN is studying the possibility of converting the A13 and A14 toll plazas (full-lane barriers and diffusers/interchanges), located in the Yvelines, Eure and Calvados départements, to free-flow. This route is ideal for large-scale deployment of free flow, given its geographical location at the end of a concession network, in an open system not linked to another toll system.

The project to convert full-lane toll plazas (BPVs), toll plazas on interchanges and toll plazas on diffusers to free-flow tolls involves removing the existing toll facilities and infrastructures and replacing them with free-flow gantries installed above the lanes on the main sections and on the branches and ramps, so as to ensure free-flow toll collection on the routes concerned.

Nos missions

The traffic study consists in assessing the impact of implementing a free-flow toll system on the A13 and A14 freeways.

The objectives of this study were manifold:

Quantification of time savings associated with the introduction of a free-flow toll system, based on FCD calculations and data;
Verification of operation and presence of any hard points resulting from the removal of BPVs through dynamic modeling.

The scope of the study covers the stretch of A13 between Orgeval (intersection with the A14) and the Caen ring road, as well as the section of A14 including the Montesson BPV.

The first part of the study consisted in processing and analyzing these data to draw general conclusions about congestion at BPV today.

The second part consisted in estimating time savings by type of user (light vehicles and heavy goods vehicles), by type of route (full-lane or slip road) and by type of gain (stopping time on BPV or time saved thanks to the elimination of traffic jams). An estimate was made for certain days identified as typical days, then the annual values were calculated by interpolation.

The third part consisted in building a dynamic model to reproduce current traffic conditions on significant days, in order to assess the impact of removing the barriers. Analysis of the model results in the free-flow configuration was intended to identify any traffic bottlenecks or the postponement of certain tail-back phenomena.