Entrance control eliminates a conflict of vehicles at the exit of the two-lane roundabout

Abstract

Traffic flows are merged, overlapped and separated in a roundabout and thus creates a conflict spots and conflict zones. Number of conflict spots and the size of the conflict area of roundabout depends on the roundabout type and the number of incoming and outgoing traffic flows. Distribution of accidents in roundabouts shows a significantly higher number of accidents at the two-lane roundabouts, compared to the single-roundabout. The number of accidents at the entrance of the two-lane roundabout is aproximately two times higher than the number of accidents at the entrance to the single-lane roundabout, which is commensurate with nearly two times larger volume of inbound traffic. However, the number of accidents at the exit of the two-lane roundabout is seven times greater than the number of accidents at the exit of the single-roundabout and could not be explained by the higher volume of traffic. This analysis of accidents shows that exits of the two-lane roundabout are road safety problem, which requires a solution. Starting from the premise that roundabout, in general functional aspect, could be seen as an input output system, and setting up road safety goal without competition in the two-lane roundabout, the model of the vehicles' entrance control in the two-lane roundabout is generated. It eliminates the dominant conflict of vehicles at the exit of the two-lane roundabout, caused by cutting the path of the vehicle exiting the roundabout, with the path of another vehicle that circulated after entering the roundabout.

Keywords

• two-lane roundabout
• entrance
• exit
• control
• vehicles' conflict crossing
• road safet