The Study On Optimization Of Urban Rapid Way By

Urban rapid way is the main framework for urban traffic network, the operating efficiency direct influence the overall efficiency of urban transport. With the rapid development of urban economy, the number of cars increasing, the existing urban rapid way can not meet the city's traffic demand, and congestion phenomena occasionally occur. It is imperative to optimize the urban rapid way, in order to ensure the operational efficiency of it. To study the optimization of urban rapid way traffic operation is of great significance. Optimization and alteration of the urban rapid way should proceed from reality. Then through the method of identification of adaptation needs about urban rapid way's size, and contacting the surrounding road network to rationally optimize and organize the traffic convergence, can effectively solve the traffic problems in urban rapid way.In this thesis, with the main theme of the optimization of urban rapid way, the tree key issues are studied which is the alteration of the scale of rapid way, the layout of rapid way entrances, and connection of the rapid way and the around city roads'(auxiliary road and main or secondary road). In the aspect of the alteration of the scale of rapid way, the"Four Stages"is used to predict the rapid way traffic demand. Then the traffic capacity is discussed. Based on the traffic demand and capacity analysis, the transformation of the scale of rapid way that is the number of rapid way drive is determined. In the aspect of the layout of rapid way entrances, the model about entrances'minimum distances is formulated, according to the principle entrances'layout and the characteristics of traffic flow at the entrances. Following, the reference value of entrances'minimum distances is calculated. In the aspect of optimization and connection of the rapid way and the around city roads, based on the study of the length of the traffic cutting which generates under the coplanarity of the main line in the rapid way and auxiliary road on the ground. The length of the traffic cutting on the ground is calculated. At the same time, the traffic organization methods about entrances and exits on the rapid way and urban road. After that, the traffic organization measures are advanced which can effectively improve the capacity of entrances and exits on the rapid way.At present, there are few researches on the urban rapid way. In this thesis, the existing traffic optimization theories are carried on the effective integration use. And the rapid way optimization method is proposed. The method is applied, and can provide a scientific reference for the design, optimization and alteration of the urban rapid way.