Predicting lane utilization and merge behavior at signalized intersections with auxiliary lanes in Buffalo, New York

Although auxiliary through lanes (ATLs) are often used to increase the capacity at signalized intersections, their utilization by motorists tends to be significantly lower than continuous through lanes (CTLs). This study was designed to (1) determine whether recently proposed models for predicting lane-drop utilization are applicable to Buffalo, New York; (2) develop new models for predicting ATL utilization and for predicting drivers' merge behavior at ATLs; and (3) assess the ability of microscopic traffic simulation models to reproduce observed merging behavior. To achieve this, geometric, traffic count, and merge data were collected from select sites in Buffalo. The study shows that lane utilization in Buffalo is a function of total through-traffic volume, right-turning volume, and upstream and downstream land-use types. The average merge distance, in contrast, tends to be a function of the ATL total length, the first lane-drop warning sign, the speed limit, and the total through-traffic volume. The study also identified the challenges of calibrating merge behavior in microscopic traffic simulation models against field observations.