Study on Traffic Incident Spatial and Temporal Influence Range Prediction on Eight-lane Freeways
Traffic incidents reduce the road capacity,increase the risk of driving safety,improve the degree of travel time delay,and harm the freeway network.The available power is different under different traffic incidents,and the dissipation scale,duration,and travel time are also different.Therefore,predicting the spatial-temporal impact and road travel time according to the incident type and traffic flow plays an essential role in reducing the adverse effect of the incidents on the road network.Through wave theory,this paper establishes the spatial-temporal incident prediction model on eight-lane freeways.We designed the simulation experiment,used active traffic data to calibrate the simulation parameters,and calculated the difference between simulation and model prediction results.The results show that for a one-way four-lane freeway with a level of service Ⅱ,when a traffic incident closes one lane or two lanes,the impact of the incident is determined by the traffic flow rate and the impact range of the incident is minor.When the traffic incident leads to half of the freeway closed,the traffic flow rate upstream of the incident changes nonlinearly due to the queuing vehicles headway reduction,and the influence of the incident is less than the calculation result.Generally speaking,when traffic incident occupies three or four lanes of expressway,the incident have a significant impact on the operation state of the road network.
freewaytraffic incidentevent durationevent radiation rangeroad travel time