Research On Establishment And Exit And Entrance Of Interchange Bridge

The quantitative technical index of combining horizontal and vertical curves of expressway,interchange selection in mountain,the interchange minimum spacing model based on the lane changing,tunnel and Interchange outlet spacing,ramp length of motorway service area entrance are researched by statistical analysi,mathematical analysis,probability theory analysis,computer simulation in this paper,and the corresponding results are obtained as follows:Because of the complex geological conditions,huge engineering quantities and other characteristics of Mountain highway,mountain interchanges,different from characteristics of the interchanges in plain area,should be laid combining the characteristics of flexible site selection and the reasonable layout.Through examples,this paper analyzes and summarizes the characteristics of mountain interchange,and according to its characteristics,it describes the general principles of making the program site selection.And through the concrete engineering practice and the specific application,it analyzes the content of each principle to reveal the core thinking of mountain interchange site selection.In the combination of horizontal and vertical alignment,this paper proposes that the necessary condition,which is to have a good line of sight and to ensure the pavement drainage,of juding the rationality of a combination of a flat and vertical surface.The basic identification sight distance on convex and concave vertical curve under driving at night and flyover are studied based on driver's line of sight guidance and the index of the vertical curve radius and length could not meet horizontal includes vertical linear combination is raised;and Based on road surface drainage,three quantitative indexes on could not meet horizontal includes vertical linear combination are presented by three aspects of longitudinal slope,cross slope drainage and pavement structure,under the Comprehensive condition of line of sight guidance and pavement drainage.the technical index of a combination of a flat and vertical surface on could not meet horizontal includes vertical linear combination are presented.In order to exert the service function of the outer ring road of the city traffic to different traffic flow,and to solve traffic problems due to insufficient space between two interchanges,the paper establishes the minimum space model between two independent interchanges.It analyzes the driver's psychological,physiological reaction process to road traffic information and establishes a driver's lane-change model.According to the survey,it works out a regression relationship between speed and the angle of drivers changing lanes.Due to traveling distance while the driver is looking for an acceptable gap to cross,it get the relationship model of the clearance between two interchanges.Referring to examples of ShenZhen Outer Ring Expressway analysis,research results show that: two close interchanges should appropriately reduce unnecessary road traffic signs.When the design speed of two-way six-lane road is 100 km / h and 80 km / h,the distance between interchanges should not be less than 1410 m and 880m;when a higher proportion of large vehicle or a seriously mixed traffic organization exists,the minimum space between interchanges should be appropriately increased 180 to 200 m.Space between Tunnel and interchange exports are affected by many factors,considering the driver's visual characteristics and the characteristic of traffic flow between tunnels and interchanges,the paper requests different distance demand in different roads,calculates each distance value of its component.And according to it,the paper brings out the clearance between Tunnel and interchange exports,instruct the new project and proposes improvement measures on the narrow distance of the already built ones.