Study On Related Issues Of Establishment At The Entrance And Exit Of Urban Expressway

In recent years, many large city began the construction of urban expressway to release the increasing pressure on the urban transport in China; in the other hand, there have been lots of problems arising due to the pressure of the increasing traffic flow in the urban expressway network, and these problems exist mostly in the area of the exit and entrance; in addition, because of the specification which is imperfections about the urban expressway, resulting in more and more problems at the exit and entrance, it seriously impacts the efficiency of the urban expressway network. Therefore, it's significance to study on establishment with related issues at the entrance and exit of urban expressway and will play a large role to benefit from the urban expressway network.First, the paper sorts the existing problems at the entrance and exit, and then analysis the source of these problems by vehicle trajectory and traffic flow line. Then, the contents of this paper were summarized, and the article is divided into three parts to be studied.In the aspect of the location of entrance and exit, for the interchange nodes, the paper studied the location of interchange with a combination of qualitative and quantitative method to determine the location of Interchange. Qualitative analysis is based on the traffic location theory, and quantitative analysis is the introduction of the concept of an important degree. For the entrance and exit which is at the road section, the paper quantify the entrance and exit according to various combinations of types of entrances and exits, then trying to build the relationship between traffic and the optimal quantity to calculate optimal quantity.In the aspect of selections of interchanges, the paper introduced the advantages and disadvantages and the application conditions of several commonly used types of interchanges, and then determined the interchange type from the following aspect:the level of the intersecting road, traffic flows and land-use restrictions and so on. The paper also demonstrated the application of composite interchange according to two examples.The design of the entrance and exit mainly include the design of the lanes and the traffic organization design, the paper analyzes the traffic organization design at the entrance and exit for different types of entrance and exit combinations.At last, the paper takes ring road of Beijing as an example from the location of the ring road, the problem of the entrance and exit, the traffic organization design to prove the previous contents feasible.