Vehicle Class Wise Service Time Prediction Models for Tollbooths under Mixed Traffic Conditions

The present study attempts to develop service time prediction models for different vehicle categories on toll plazas in India under mixed traffic conditions. Service time includes the time elapsed in transaction of toll tax and time required by a vehicle to travel a distance equivalent to its own length. Field data are collected at fourteen different lanes at three toll plazas in different region of the country by the video recording method. All vehicles in the traffic stream are divided into seven categories. The service time values are obtained as low as 2.64 seconds (s) to as high as 58.76 s for small car and trailer respectively. This variation in service time is dependent on random arrival of vehicle at tollbooth and drivers and tollbooth operator's personal attributes and therefore simultaneous equations are developed to relate service time of a vehicle type with the traffic volume and its composition. These equations are solved for some assumed values of traffic volume and traffic composition and effect on the service time of each vehicle type is explained. Accuracy of the service time values estimated through equations is checked by comparing the estimated value with those calculated directly from the field data. The service time models proposed in the present study may be useful for planners and managers for designing and evaluating the performance of toll plazas.