Modelling Capacity of Signalized Intersections with Congestion

Headway distribution is an important way to study traffic flow.Based on the traffic sample data of several intersections in Beijing,this paper analyzes the headway distribution of vehicles which cross the stop in the queue with congestion and its changing characteristic.Result shows that it reaches saturated headway since 6th vehicle.On this basis,a traffic capacity model with congestion is built,and it's for the signalized intersections which are formed by arterial or subordinate roads at city center areas.Further,the data surveyed at some signalized intersections is used for case calculation and contrast.The result is that the average error rates of going straight and turning left traffic capacity are 2.27% and 4.28%,which verifies the feasibility and effectiveness of the model.In addition,the result of this calculation method is superior to others,which shows that the method is of higher applicability in the congestion state.