Delay modelling at manually operated toll plazas under mixed traffic conditions

Abstract

Toll plaza operations in India are entirely different from that of the United States (US) and European countries. The majority of tollbooths in India are manually operated, where all the vehicles arriving at the toll plaza have to stop at tollbooth to pay the toll. During this process, a vehicle first decelerates, joins the queue and pays the toll at tollbooths. Afterwards, the vehicle accelerates and regains the stream speed. The overall process causes delay to each approaching vehicle due to deceleration, waiting time in the queue, service time at the tollbooth and finally due to acceleration. Hence, the present study aims to quantify the overall delay that includes system delay (service time and waiting time), acceleration and deceleration delays at manually operated toll plazas under mixed traffic conditions. The overall delay model has been proposed by using (i) dynamic acceleration and deceleration values, (ii) waiting time in the queue and (iii) service time depends upon traffic composition and approach volume. The delay thus obtained from models has been validated from field observed delay values and it is found that no significant difference between observed and predicted delay values. Therefore, the proposed delay model can be used in future to quantify the vehicle delay at toll plazas and can also propose Level of Service (LoS) thresholds and the number of tollbooths required for prescribed LoS.