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A coordinated control framework of freeway continuous merging areas considering traffic risks and energy consumption
Weihua Zhang1, Fan Zhang1, Zhongxiang Feng1
1School of Automotive and Transportation Engineering, Hefei University of Technology, Hefei 230009 China.
Accident; Analysis and Prevention
|January 22, 2025
Summary
This study introduces a coordinated control model for freeway merging areas to reduce crash and congestion risks. The new framework significantly improves traffic safety and efficiency on highways.
Area of Science:
- Traffic Engineering
- Transportation Science
- Operations Research
Background:
- Freeway continuous merging areas with multiple ramps present complex traffic dynamics, leading to frequent crashes and congestion.
- Existing active traffic management (ATM) strategies like variable speed limit (VSL) and ramp metering (RM) often address these issues independently.
- A comprehensive approach coordinating VSL and RM for overall risk mitigation in merging areas is underexplored.
Purpose of the Study:
- To develop and evaluate a novel Bi-level Programming Model for coordinating VSL and RM control strategies.
- To comprehensively mitigate traffic risks, including crash and congestion risks, in freeway continuous merging areas.
- To enhance traffic safety, operational efficiency, and reduce energy consumption.
Main Methods:
- Development of a Bi-level Programming Model: Upper-level for VSL control (minimizing crash risk, congestion risk, energy consumption), lower-level for RM control (minimizing ramp congestion risk, energy consumption).
- Utilized an extended Cell Transmission Model (CTM) for simulating traffic flow under VSL and RM control.
- Integrated a traffic risk evaluation model with the bi-level coordinated control model.
Main Results:
- The coordinated control framework significantly reduces average crash risk (ACR) by 14.10%.
- Demonstrates a 19.52% reduction in average mainline congestion risk (AMCI) and an 8.86% decrease in average energy consumption (AEC).
- The proposed method outperforms existing control strategies in enhancing freeway safety and efficiency.
Conclusions:
- The Bi-level Programming Model effectively coordinates VSL and RM to manage risks in freeway merging areas.
- The developed framework offers a significant improvement in traffic safety, efficiency, and energy consumption.
- Potential application for active and coordinated traffic management systems on freeways.
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