Circulatory Markings at Double-Lane Traffic Roundabout: Comparison of Two Marking Schemes

This paper compares two types of circulatory markings at a double-lane traffic roundabout: the concentric marking scheme and the Alberta marking scheme. The effects of these two marking schemes on drivers’ lane choice behavior, delay, and safety, are compared based on data collected from before and after field surveys over a period of 2years. The results showed that the Alberta marking scheme could better balance the traffic flows on the two circulatory lanes, resulting in higher performance levels.