Research On Reliability Of Urban Road Network’s Level Of Service

The definition of urban road network reliability is:various traffic service of road network ’s ability to meet the demand of network traffic in the stipulated time and the prescribed conditions. As China’s urbanization process and continuously push forward the urban road traffic is increasing rapidly, the pressure on the transport system is also growing, the reliability of the transport system will be more and more attention.Systematic analysis of the sources of uncertainty in the road network is the basis for the reliability study of the road network, road network of sources of uncertainty mainly includes three levels of link capacity, traffic demand, traffic behavior. Uncertainty analysis in the transport network on the basis of a variety of reliability evaluation to make a simple analysis of the level of service of the road network reliability depth study:the road network reliability research focuses on connectivity reliability, travel time reliability and capacity reliability3, these three indicators is not comprehensive due to consider the issue is difficult to comprehensively reflect the randomness of the road network, the service level reliability from the travel of individual interests and the system administrator global interests point of view, considering the uncertainty and dynamic nature of the traffic demand and the capacity of the road network can adapt to the traffic state time-varying, and comprehensive response to the overall performance of the road network, traffic researchers evaluate network performance of a powerful tool. In this paper, the impact of traffic flow uncertainty on network reliability, the most likely state of the network-based generation algorithm, random supply, random demand and road network information induced level of service reliability-depth research.The single reliability evaluation generally only evaluate the performance of a particular aspect of the transportation network system, but not enough to embark on a comprehensive and integrated evaluation of complex transportation network. Travel Time Reliability is a measure of an important indicator of the random performance of the road network, road network level of service reliability expand further research, this paper, considering the travel time reliability and service levels of reliability characteristics constructed based on travel time reliability of the road network level of service reliability analysis method in order to better and more comprehensive evaluation of the performance of the road network.