Analysis of preferential treatment for public transport at intersections controlled by traffic lights

Context: This work presents the possible optimization of passenger transportation at one intersection in San Jose, Costa Rica through the application of preferential treatments for public bus transportation, through the use of a simulation program compatible with said treatments. The main indicator used corresponds to the average delays per passenger; these delays were obtained at intersections with and without the use of preferential treatments. Methodology: The input data correspond to vehicle counts that were carried out with the help of video cameras at intersections; Data were obtained, by vehicle type, for the morning and afternoon peak hours. The intersections were recreated according to the site geometry and modeled, the volumes were entered into the simulation model. In order to simulate preferential treatment, bus detectors were added to the simulation, whose function is to detect the moment in which the bus passes and with this modify the phases of the traffic light to instantly benefit the bus. The strategies used to give bus phase priority (TSP) are green time extension and red suppression. Results: In the simulation models created, preferential treatments were determined to reduce average delays per passenger by up to 38 % at the intersection studied. Annual savings in time and fuel of up to 60 thousand dollars were determined. Conclusions: Calculating delays per person, instead of the traditional calculation per vehicle, can provide a different perspective to the analysis of capacity at intersections. The implementation preferential treatments for transit could be feasible in economic terms.