Real-Time Risk Assessment Model of Freeway Traffic in Rain and Fog Weather


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According to the relative position between before-after vehicles or vehicles and obstacles after braking, a separate vehicle risk in different traffic flow states is divided into four levels. To discriminate real-time traffic status on road sections , the concept of critical density is brought in and the risk of four ranks corresponding to the critical speed are anti-calculated in free driving state and car-following state. By comparing critical speed with the average speed on road section, separate vehicle risk is converted into real-time risk of group vehicles, and real-time risk assessment model of highway traffic in rain and fog weather is established. Simulation results show that the low-density traffic flow will bring lager risk than high-density traffic flow in rain and fog etc disastrous weather; To reduce traffic risk of road section, effective measures are speed limit in low-density flow, speed limit in combination with shunt in high-density flow



Edited by:

Chunliang Zhang and Paul P. Lin




F. Guo et al., "Real-Time Risk Assessment Model of Freeway Traffic in Rain and Fog Weather", Applied Mechanics and Materials, Vols. 226-228, pp. 2370-2375, 2012

Online since:

November 2012




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