Widening the scope for bus priority with intermittent bus lanes

In the search for improved flowing conditions for buses, many cities have introduced bus lanes and incorporated bus priority schemes in their traffic control systems. However, these two instruments are insufficient in themselves, since bus lanes are not justified with a low frequency of buses but without such lanes buses frequently have to travel in congested conditions in extended parts of their routes. This paper presents the concept of Intermittent Bus Lane (IBL), suggests that it could be physically implemented with longitudinal traffic lights, discusses its fields of application and points to the mathematical solution of some of the most relevant control problems associated with it.