La Défense business district was built on the basis of a separation between the pedestrian flow on La Défense slab with the accesses to the towers and the flow of vehicles in the basement.


This results in a whole set of covered access lanes with different usages: service, deliveries, transit, public transport. These lanes, of very variable lengths and geometries, represent more than 6 km of covered lanes in total. From a safety point of view, these lanes are assimilated to road tunnels with regards to the French Roads standards. They have been the subject of previous diagnosis studies and safety improvement program proposals.


However, before carrying out these programs, the local planning entity (EPADESA) wished to clarify certain bases and harmonise traffic regulations with two objectives: make the site more user-friendly and, taking into account the constraints of the site, reduce the risks.


In fact, harmonising and limiting the size of vehicles, or even reducing the size of vehicles by limiting their total authorized loaded weight makes it possible to reduce the fire risk by limiting the heat potential. Therefore, allowing to update the prevention and protection measures in order to save money.


Thus, EPADESA wished to carry out a set of preliminary strategic studies to define its constraints and its assumptions, and generally to consolidate the proposals resulting from the previous studies.




setec tpi is teamed in a consortium with setec ITS and performed Project Management Assistance (AMO), the objective was to carry out a set of structuring studies for all the covered tracks of the La Defense site. More specifically, it included the following services:

  • Study of the opportunity for a public transport system within the covered tracks,
  • Critical analysis of all the studies diagnosis and previous proposals, including the budget analysis,
  • Study of the opportunity of harmonizing gauges on all tracks,
  • Study of the effects of a truck fire according to its PTAC (vehicle authorized full load) and therefore the opportunity to limit the PTAC,
  • In the event of a fire, study to compartiment, which is ways of isolating the spaces of the covered tracks from the neighbouring areas
  • Interface studies, for example with the A14 motorway for ventilation plants or the interaction of roofing structures in the Coupole-Regnault district.


A consultation took place, with the support of setec organization, with the site’s stakeholders, particularly the tracks operator (Defacto), the institutional stakeholders (Unibail, CNIT, Quatre Temps) and the users (local associations for example).


Key information


Client: Establishment for the Development of La Défense – Seine Arche (EPADESA)

Cost of studies: € 377,200

Duration: mid 2011 – end 2012


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