The Analysis of the Influences of the Double Parking Vehicles to the General Traffic Flow

In some Europe cities, like Lisbon, Portugal, many paid and non-paid roadside parking lots have been constructed, but it is still not enough and often happens some temporal parking vehicles on a lane where otherwise vehicles could be freely moving or even double parking just beside the roadside parking lot, therefore the general traffic flow are influenced. After having investigated the practical cases in some areas of Lisbon, it is found that the situations are much more complex, specially during the peak hours, as most drivers do not want to switch lanes till they are near the parking vehicle. Also, for an individual parking vehicle, it might be located at different places, being near or far away from the intersection, and with different parking time, being in few minutes, or even more than half hour. In a same lane, it may also appear more than one illegal parking vehicle. This paper first has analyzed its influences to the whole traffic flow, then using software VISSIM on related mathematic models and traffic characteristics in Lisbon to find its influence to individual vehicles. Finally, a case study in an area of Lisbon based on the practical detected data is shown.