DETERMINING THE LATERAL DEPLOYMENT OF TRAFFIC ON AN APPROACH TO AN INTERSECTION

An analytic model that predicts the lateral (i.e., lane-specific) deployment of traffic on an approach to an intersection is described. The basis for this model is a variation of Wardrop's first principle: that every motorist will select a lane on an approach consistent with his or her intended turn maneuver and with any specified lane channelization so as to minimize his or her perceived travel time. The specified conditions include the approach geometry; lane channelization, if any; specification of control policy at the intersection; service rate for each turn-movement component of the traffic stream; and turn percentages of the traffic stream discharging from the approach. The model yields the proportion of the total traffic volume entering the approach that is deployed in each lane, stratified by turn movement. The model is one component of a larger analysis that predicts the capacity of an approach and, by aggregation, intersection capacity. A brief outline of this capacity model is also included. (Author)