Modelling of Bosporos bridge toll plaza with AIMSUN microscobic simulation software

Microsimulation programs have been in use for many years in developed countries around theworld. They are primarily used in designing various transportation projects and theirproductivity analysis, for selecting among alternatives, and for current state evaluation oftransportation facilities. One of the prime objectives of this thesis is to demonstrate thebenefits of microsimulation, and to show the necessity of modeling before the fieldapplications so that possible losses due to inappropriate practice will be prevented beforehand.The Bosporus Bridge is a toll facility for passenger vehicles only. Tolls are paid at a plazawith 13 toll lanes located at the Asian exit of the bridge. Toll lanes are grouped according topayment types. At the time of this study, there were five OGS (or A-Pass, electronic lane),one KGS (passing System with a card) and seven manual lanes. The performance of the plazadepend on the number of toll lanes in terms of payment type and their position within theplaza. Due to promotions offered lately, the rate of OGS utilization increased to Level of55%-65%, and this rate tends to increase more.Vehicle queues and delays at the Bosporus Bridge toll plaza led us to question whether theplaza has been used efficiently, and whether the number of toll lanes is appropriate given thetraffic composition. We developed a simulation model of this plaza using the AIMSUNmicroscobic simulation software,and conducting experiments regarding various alternativescenarios with this model. One of the result obtained is that for the current traffic compositionwith respect to payment types, the number of OGS (electronic) lanes is excessive (i.e., morethan needed). This present configuration causes vehicles to decelerate due to extended queues,and results in results in reduction in the performance of the plaza. Only in case that OGS rateincreases more than 15% with respect to present traffic composition, adding one more OGStoll lane increases the efficiency slightly.Key words: Microsimulation, AIMSUN, Bosporus Bridge, Toll plaza, Electronic tollcollection.