Abstract : Since the nineties, town centers have been characterized by a decreasing of speed transport with the implementation of public transport infrastructures. Considering this context, the concept of gravity-based accessibility is used to understand this recent phenomenon.
In a theoretical part, this research aims at demonstrating that gravity-based accessibility measures are consistent with the surplus theory. In an empirical part, this research assesses the impact of a new transport policy (with a tram network implementation) on job-access level for car and public transport users. Computations are made on Strasbourg area and are based on a modeling method with a GIS and a four-step model.
Two types of results are underlined. First, the thesis permits to apply gravity-based indicators for the two modes considering a fine zonal grid and a congestion charge. Secondly, it tests two of the various mode alternatives proposed to workers living in Strasbourg. In spite of an improvement of the public transport network, car is the best mode to access to the whole area. Nevertheless job-access is higher by public transport than by car to access the town center. Territorial inequalities remain important for public transport users. Prospective scenarii are implemented (urban toll, car-tax, speed limitation on highways and motorways, improvement of public transport speed) to reduce the job-access differential between the two modes. The decreasing of travel time in public transport offers the best results.