Analysis Of Bus Headway Stability Based On AVL Data

With the development of urban to large,the traffic congestion and environmental pollution has become a realistic issue to be considered,whereas the priority to develop public transport has been recognized by all countries as the best strategy to address the growing demand for travel among urban residents,this way can greatly resolve the urban congestion and environmental pollution simultaneously.The stability of headway is one of the most important factors in the reliability of public transport service,not only have an impact on travel time of passengers but also can avoid empty driving,the stable headway can improve the utilization efficiency of vehicles and play a very important role in enhancing attraction of bus and improving the efficiency of the bus.At present,the advanced Vehicle Positioning System can monitor the vehicles in the road network and output traffic information such as position,direction of flow,traffic volume and flow rate,the system can also carry out the real-time traffic guidance and traffic flow organization optimization,at the same time,a large number of off-line data is also retained,which provides a new data environment for the study of the stability of the headway.AVL,GIS and AFC data are used in this paper,the stability analysis of bus headway is the research objective.The study is carried out from three aspects: the evaluation of headway stability,the influence factor analysis of headway stability and the optimization suggestion.First of all,the intelligent bus data is the basis of the research problem,this paper extracts the intelligent bus offline-data of ChengDu and develops the process of data preprocess to obtain the data set that can be used for research.Secondly,from the point of view of the station,line and network,the paper aims at the stability of headway and proposes index of headway eviation consistency,headway adherence index,probability of bus bunching to describe the stability of headway qualitatively.Combining with the actual data of line 3 in ChengDu,this paper discusses the calculation method and relation of the headway stability index in the data environment of intelligent bus.On the basis of the selected indicators and analysis,the influence factors of the headway stability are quantitatively analyzed by using the linear multiple regression model.Results show that the departure intervals,bus lanes,station number,time variable,the distance between the sample point and the origin station,signal numbers between the station and first station,number of vehicles in same station have great effects on headway stability in different models.Finally,this paper studies the influence degree of the time interval,the location of the station,the green split and the cycle length of signal intersection on the headway stability by using Vissim simulation model and the control variables.The results show that the influence of position on the headway stability is not obvious,and the other three variables have obvious influence on the headway stability.Combining with the reults of chapter 4,this paper puts forward that setting reasonable frequency of departure,the number of bus in same station,the green split and the cycle length of the signal intersections have a great effect on the headway stability.