Analysis of the relationship between aggregated traffic volume and traffic conflicts on expressways

Abstract

Numerous efforts have been made to examine the relationship between aggregated traffic volume and conflicts and some inconsistent findings (linear vs. non-linear) have been observed. In this study, we explore the causes of this inconsistency. It is found that traffic conflicts are very similar for all uncongested traffic states, which supports the proportional linear assumptions in many research. By contrast, the conflicts for congested traffic states are significantly higher, which results in a non-linear feature for combined traffic states.

Keywords:

• traffic conflict
• time to collision
• traffic state to conflicts relationship

Acknowledgements

We are indebted to the journal's Editor-in-Chief and three anonymous reviewers whose comments significantly improved the earlier version of this manuscript.

Notes

1. For simplicity, only middle-lane data were collected and used in this study.

Additional information

Funding

This work was jointly supported by the National Natural Science Foundation of China [grant number 51208462] and the Key Science and Technology Innovation Team of Zhejiang Province [grant number 2013TD09].