Study On The Layout And The Type Selection Of Interchanges Of The Urban Road Network

With the promotion of the urbanization process and the population highly gather on the space, the contradiction between traffic demand and traffic supply is becoming sharp Study on the layout and the type selection of interchanges of the urban road network has important to linking up the road networks at all levels rationally, promoting the network of urban road to give play to benefit of the network, balancing the flow of road network effectively, arranging the construction fund rationally and guiding the follow-up design work at stage effectively.This paper reviews the development status of interchanges, general research situation of interchanges'layout and type selection in our country and at abroad,and study the connection of urban space evolution , urban traffic and the system of interchanges , confirms the function of the interchanges, divises the grade and analyse the characteristic on the interchanges.In the course of layout planning, combine the three aspect of macroscopic, middle-level, microcosmic, receive the method on the layout planning of urban interchanges. It is Considered on the connection the urban land, urban traffic nature, the arrangement form of urban road, city macroscopical space view .In the middle-level, this paper analyses road grade, the minimum interval terms ,etc. Finally, consideres coordinately the two respects of the volume of traffic of the crossing and the capacity of local environment.In the course of the type selection of the urban interchanges,the paper summarizes the general formula .On this basis ,It analyses the technical indicators such as the traffic capacity and the speed of design ,etc.and make summary on the pluses and minuses to every basic form. In order to selecte the suitable types, 20 models are selected to pay form go on cluster's analysis and are divided different classification.In line optimize respect of appraising, it sets up the index system of synthetic evaluation and simply introduces the evaluation methods of panning scheme of single interchange.It introduces the analytic hierarchy process,primary component analysis to evaluate the layout and the type selection of urban interchange synthetically.