Relationship between Weaving Length and Traffic Safety in Road Interchanges

Weaving areas in road interchanges are dynamic areas, where vehicles change lanes frequently to complete merging and diverging operations in a short distance. As a result, traffic flow is rather unpredictable and volatile, with negative impact on the safety and efficiency of the entire interchange. This paper studies the impact of weaving length on traffic safety and efficiency. An orthogonal experimental design is developed in order to analyze the relationship between traffic conflicts and (i) weaving length, (ii) traffic volume and (iii) ratio of weaving volume to mainline flow. A microscopic simulation model, VISSIM, is used to model the Youyi Avenue interchange of Wuhan Changjiang River Tunnel and extract the selected as the traffic safety indices for each scenario, i.e. traffic conflicts and conflict velocity. Finally, a reasonable weaving length for the interchange that balances traffic safety and efficiency is estimated using the difference analysis method.