Estimation method of average travel time for road sections

In order to availably utilize loop data and estimate the average travel time of road sections accurately and quickly, an estimation method of average travel time was proposed. Average travel time was divided into average running time, average queue delay and average crossing intersection time. Average running time was calculated by using average speed based on taking account of the installation type differences of loops. Piece-wise time homogeneous Poisson process was used to describe the arrival and departure processes of vehicles, Markov model was used to describe the queue process of vehicles, birth and death process was used to model vehicles' number in queue, and two kinds of average queue times with initial queue and no initial queue were computed. Average crossing intersection time was computed based on average vehicle length and saturation volume rate at intersection. Computation result shows that the relative error between the measure value and computation value of average travel time is less than 12%, so the method is feasible.