A mathematical model for traffic on a two-lane, road, is used to derive traffic characteristics such as average speed of vehicles with given desired speed, average number of passing's average flow, and speed distributions for "free" vehicles from parameters such as density of vehicles in each lane, distribution of desired speeds, maximum speed of oncoming traffic, relative passing distance, minimum sight distance and average number of jumps of the sight function. Some estimation problems are discussed and the model is applied to empirical data. The data was gathered on the same road for the different speed limits and for no speed limit as well. Some support for the applicability of the model is obtained e.g. from the fact that the estimated distributions of desired speeds are consistent with the various speed limits. When applicable the model can be used in traffic and safety studies to calculate the effect upon various traffic characteristics of measures such as increased visibility or speed limits.
Abstract