Highway Intersection Traffic Conflict Analysis

Intersections are important hub point of the transportation net. The traffic composition is relatively chaotic in that place.And the traffic characteristics are very complex.It is prone to accidents at intersection. Use traffic conflict technique to evaluate the safety of intersection, more samples can be collected in short time.This the randomness will reduce and the risk period will be shortened.Based on the collection of large amount of survey data, this paper first analys the relationship between the intersection type and the traffic conflict, then get the contect between the number of intersecting roads and the number of traffic conflict points; The smaller the crossing angle, the greater the extent of the conflict; The closer the intersection of road grade, the greater the probability of conflict; The signalized intersections seemed to reduce the number of conflict points. Second, quantify the relationship between the intersection traffic flow characteristics and traffic conflict, namely to consider the impect of the total traffic flow, road traffic intersection ratio, the proportion of large vehicles and vehicles to turn left proportion for the conflict; When fitting traffic speed distribution model and the main road headway distribution modle, combined with gaps identified the capacity of branch; Analys the driver’s psychological and physiological characteristics in different traffic flow conditions, establishing waiting time and accept gap model. Again, select severl factors which have important effect on the intersection safty; according to the fuzzy set theory, then introduce triangular fuzzy number judgment matrix to determine the weight of each factors; A modle which consider the rode conditions and the traffic conditions and the driver’s choice was build based on traffic conflict theory, and with this modle eveluate the safty of Daxin-Xishuo intersection. Finally,try to improve the geometry condition and traffic flow organization of the intersection, analyzing the future traffic flow, traffic composition and the actual terrain and the surrounding architecture of Daxin-Xishuo intersection. An improvement plan was given for that intersection.