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Modelling and Mitigating Secondary Crash Risk for Serial Tunnels on Freeway via Lighting-Related Microscopic Traffic
Shanchuan Yu1,2, Yu Chen3, Lang Song1,4
1National Engineering and Research Center for Mountainous Highways, China Merchants Chongqing Communications Research & Design Institute Co., Ltd., Chongqing 400067, China.
International Journal of Environmental Research and Public Health
|February 25, 2023
Summary
Secondary crash risk in freeway tunnels is reduced by adaptive lighting and connected vehicle guidance. These strategies mitigate traffic turbulence and improve visibility, especially near tunnel portals and queues.
Area of Science:
- Traffic engineering
- Road safety
- Intelligent transportation systems
Background:
- Secondary crashes (SC) pose a significant risk in freeway tunnels, exacerbated by traffic turbulence following primary crashes (PC) and varying lighting conditions.
- Location-heterogeneous lighting and inter-lane traffic dependencies complicate SC risk assessment in serial tunnel environments.
Purpose of the Study:
- To model and mitigate secondary crash risk in serial freeway tunnels.
- To quantify SC risk using a traffic conflict approach and simulated vehicle trajectories.
- To evaluate the effectiveness of adaptive tunnel lighting control (ATLC) and advanced speed and lane-changing guidance (ASLG) for connected vehicles (CVs).
Main Methods:
- Development of a microscopic traffic model incorporating lighting conditions and inter-lane dependencies.
- Quantification of SC risk using a surrogate safety measure based on simulated vehicle trajectories post-PC.
- Numerical simulations to analyze SC risk patterns and assess countermeasures.
Main Results:
- High-risk locations for SC include the tail of traffic queues, adjacent lanes, and areas near tunnel portals.
- Adaptive tunnel lighting control (ATLC) is more effective than advanced warnings for CVs in mitigating SC risk.
- Combined ATLC and ASLG strategies show promise in reducing SC risk by managing traffic turbulence and lighting variations.
Conclusions:
- Integrated ATLC and ASLG effectively mitigate SC risk in serial tunnels by addressing both immediate traffic responses and environmental conditions.
- Optimizing lighting conditions and providing timely guidance are crucial for enhancing safety in tunnel environments post-primary crash.
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