On Setting Line Frequencies and Capacities in Dense Railway Rapid Transit Networks

The tactical determination of line frequencies in railway networks is usually carried out as a by-product of the Line Planning phase within the general Railway Planning Process. The classical approach need to solve a previous network loading model in order to determine the different paths followed by users in their trips. Then, frequencies are determined assuming a fixed capacity both in vehicles and infrastructure. In this work, we present a general optimization model hat simultaneously determines lines frequency and trains capacity without supposing an a priori passenger behaviour with regard to route choice decisions. The aim is to minimize travel time, transfers and operation costs considering both the user and the service provider points of view. In order to deal with infrastructure capacity, the model also allocates lines to tracks in multi-line open tracks. A little example is used in order to illustrate the model capabilities.