Operational Performance at Two-Way Stop-Controlled Intersections

Abstract

When two cars approach the stop-controlled legs of a two-way stop-controlled (TWSC) intersection at the crossing of a major and a minor roadway, driver perception concerning which vehicle should be granted the right-of-way is often unclear. This confusion can increase if one of the drivers intends to execute a left turn. The research described in this paper was performed primarily to identify any safety issues with driver perception or understanding in the case of one left-turning vehicle with an opposing right-turning or straight-through vehicle at the stop-controlled legs of a TWSC intersection. The data collection involved filming and observing vehicle interactions at seven TWSC intersections in the cities of Bryan and College Station, Texas. The way left-turning vehicles responded to the TWSC intersection when an opposing vehicle was present was specifically evaluated. This scenario occurred 113 times for the seven intersection locations during a total evaluation period of approximately 25 h. For these 113 observations, the researchers performed statistical analyses and determined that the minor roadway volume and the first vehicle to approach the intersection significantly influenced driver behavior. The overall study findings confirm the hypothesis that drivers do not fully understand the appropriate (legal) maneuver protocols when stopped at TWSC locations.