Research On Reliability Of Urban Road Networks

Along with the advance of urbanization, the population scale grows quickly and the number of motor vehicles owned is sharply rising, which brings more pressures and challenges to urban traffic. Evaluating the service capability of the urban traffic system contributes to reasonable planning and designing the road network; shoring up the weak points in the existing road networks system to heavily protect and improve; ameliorating the strategy for traffic route guidance and controlling; providing high-quality transportation service; and finally promoting the harmoniously and sustainable development of the city.The research on traffic system applying complex networks theory dated from the 1990s, and focused on finding and confirming that the traffic system has the small-world characteristics and scale-free characteristics. The research on reliability of traffic system just sprang up in the last decade, which includes air transportation system, urban rail system and urban road system. Because the urban road system involves numerous factors, its operation rule is the most complex. In addition, the research process is very short, and the achievement about road networks reliability is scattered, thus the theory needs to be promoted and enriched.This paper at first summarized the progress and the acquired achievements of the research on transportation system reliability, analyzed the influencing factors to the reliability and the complexity of the research. Then, based on the work, introduced the complex networks theory to discuss the resolutions, combined it with the features of the traffic system to construct urban traffic complex weighted networks model, and put forward relevant appraise indexes from three aspects: survivability, stability and validity. What’s more, it took parts of Beijing urban area for example to empirical study, and demonstrated that the proposed appraise indexes are reasonable and effective. At last, after summarizing the conclusion, presents the direction for the next researches.