Study On Reliability Of Urban Public Transportation Network

Along with economic and social development, the urbanization process has been an inevitable trend. At the same time, traffic demand increases sharply. Due to space constraints of urban land use, increasing supply isn't an effective way to ease traffic pressure.Development of urban public transportation can not only improve the whole city function, but also use road resources effectively. So it will be an important way to ease urban traffic congestion. Common public transportation is a main component of the public transportation system. It's closely related to the daily life of urban residents. The next 15 to 20 years will be a changing critical period in city traffic structure and pattern. How to improve public transport travel share and quality of service? How to establish the priority of public transportation? How to attract more residents to mass transit way? These will be research hot in traffic field.Public transportation system is affected by a variety of random factors, such as weather conditions, traffic accidents. Therefore it is randome and complex. The research on reliability of transit network always starts from the operations situation at home and abroad, but not from the public transportation network and the layout of the network topology which are the most fundamental aspects.Based on summarizing research results of reliability analysis domestic and abroad, this dissertation analyzed actual situation in Jiujiang, discussed characteristics of public transportation network, screened major influnce factors on the reliability of public transiti network, and discussed reliability system info establishment on urban transit network, then defined some reliability indexes using reliability indexes of road network for reference. These indexes were public transportation network connectivity reliability, travel time reliability, nonstop reliability etc. In the end, the paper provided calculation method to every index, while probability target was brought into mathematical model.Research on public transportation network reliability has important practical significance to evaluate the network structure, and to optimize the public transportation network. Through research, existing resources can get a reasonable allocation, and the service level of the public transport system can be improved. Taking public transportation network of Jiujiang as case, the paper reached every index reliability probability value. The conclusion has promoted significance.