Study On Technique Of Mountaincity Interchange Reconstruction And Extension Based On Smooth Flow Of Traffic During Construction

In mountain city,the width of road is relatively narrow,the traffic volume is increasing,the capacity of transporting traffic of some interchange built years ago is traffic throat.Although the transport sector has adopted a variety of traffic organization,that can not solve the problem,which is even more apparent in the peak hours.The crowded lead traffic speed downand more fuel consumption of vehicle occupant.In that case,it not only greatly reduce the road capacity,but also lead to rapid increase in traffic accident rate.At present the interchange need to be reconstruction immediately,but the interchange renovation project in mountain city often bring great pressure on urban transport.If the design of the construction can be done at all stages of the construction the traffic keep flowing,it reduces the impact of social and economic benefits to the greatest extent during the construction period.Based on the construction of Lijia Garden in Chongqing,this paper studies the technology of the smooth flow of traffic duringthe interchange reconstruction and extension.Firstly this paper analyzes the programmes of interchange reconstruction and extension project.This section summes up the characteristics of mountain cities,road network and interchange.This paper analyzes several factors of the interchange reconstruction and extension,such as saturation of traffic capacity,road network transformation,limited interchange function and low overhaul standard,then illustrate it by examples.At last analysis the principle of interchange reconstruction and extension design,the program type,the comparison of interchange reconstruction and extension,the program design process.Secondly,this paper studies on the traffic organization plan of the mountainous city interchange construction.According to the different interchange reconstruction and extension projects summarize the main contents of traffic organization from the micro and macro perspective.To ensure the construction and traffic operate correctly,adopting the methods as road network diversion,reasonable construction program,construction technology,reasonable division of the construction phase.The paper analyzes several types of transportation organizations,like fully enclosed traffic organization,fully opened traffic organization partially open traffic organization,and analyzes its advantages and disadvantages.Then analyzes on reconstruction of interchange of traffic organization design process,this paper separately studies the separated interchange and interchange reconstruction and expansion traffic organization design.Thirdly,this paper studies the traffic capacity of the mountain city interchange reconstruction and expansion project in all phases,including the capacity of the ramp,the capacity of the main line,the capacity of the interweaving area and the capacity of the interchange.And this paper assess the service level,as the level of service on the ramp,the main line of service levels,the service level of the intertwined area,the level of service(13)Finally,according to the construction project of Lijia garden interchange,this paper simulates the traffic capacity of interchange in the all stages of reconstruction and extension by VISSIM.It is proved that the problem of traffic congestion can be solved by the reasonable programmes and traffic organization of interchange reconstruction and extension project.