Research Of The Traffic Conflict Model Based On The Critical Conflict Area

With the rapid development of car ownership, the traffic is increasing. The vehicle and the road are serious imbalanced. Besides coupled with poor traffic management and other reasons, traffic accidents are frequent and there is an increase in the number of casualties. Traffic accidents have become a major worldwide pollution, traffic security issues have gradually become one of the key research topics of many scholars domestic and abroad. Because the accident is the result of many factors, the occurance of traffic accident has some chance, so the data obtained from accident statistics can not accurately reflect the level of traffic safety, which will mislead the evaluation and decision-making. The datas are often unable to perform microscopic analysis. With this method there is a big accident drawback and limitation on road safety assessment. There is a big correlation between traffic conflict and accident.Traffic conflict can be a good characterization of the safety level of road traffic accident. It also can overcome the shortcomings of existing data deficiencies and long cycle. This method can quantitativly study the security situation of road infrastructure, with the feature of "big samples, short-period, small area, high reliability,". So it is increasingly favored by researchers.Traffic conflict discrimination is directly related to the safety evaluation of the intersection。 The accuracy of the traffic conflict discrimination is the key of traffic accidents prediction, the correct prediction is in favor of early measures to prevent; while the accidents prediction is one of the main contents of the traffic safety evaluation. Therefore, the accurate identification of conflict can provide a strong basis for the traffic safety evaluation and diagnosis. Scientific research of traffic conflict discriminant model can fundamentally improve the accuracy and effectiveness of traffic safety evaluation.It is the effective way to prevent traffic accidents and improve traffic safety level.This paper focused on the critical situations of conflict between vehicles when a vehicle was seen as a particle,,as well as considering the size of the vehicle.Then I established a critical conflict zone model based on the type of vehicle,and the influence on the conflict radius of each model parameters were analyzed. Furthermore, because of the particularity of the turn of articulated vehicles, I focused on the analysis of conflict situations when encoutering with articulated vehicles, and found a safe distance formula fo articulated vehicles. Therefore critical conflict model was improved. Then using the fuzzy theory to judge the severity of traffic conflict, getting traffic conflict fuzzy sets.Then I developed four rating scale,including deceleration distance between vehicles and conflict severity, related to safe passage, the general conflict, moderate conflict and severe conflict.After that step,I established a membership function of each index. Finally,I analysed the traffic conflict instances of bajiao amusement park intersection to verify the correctness of the model.