Study On Reasonable Density Of Separated Intersection Engineering Of Expressway

With the rapid development of expressway in China and the characteristics of all the expressways that control access and must be barred,expressway to some extent separate the production and living areas of residents along the line,bring inconvenience to the lives of residents along the line,hinder and divide the economic exchanges and development of the two sides.The separation of residents along the expressway can be eliminated by setting up separate intersection engineering.However,the density of separate intersection engineering is too high,even affect the safety of Expressway and increase the average filling height.If the density of separate intersection engineering is too small,it will cause inconvenience to the life of residents on both sides of the expressway and even reduce the communication between residents on both sides.Therefore,based on humanization,safety and economy,this paper studies the reasonable density of separate intersection engineering.This paper defines the separated intersection engineering of expressways,analyzes its functions and types,discusses the selection principle of separated intersection engineering types and its main influencing factors,studies the factors influencing the density of separated intersection engineering of expressways,and classifies the density of separate intersection engineering on the basis of considering the specific factors limiting the minimum density and maximum density.Based on the maximum detour distance and other influencing factors,the minimum density model of the overpass and the passage is established.Based on the mathematical model of factor analysis and the importance of nodes,the minimum density model of grade separation was established.Combining these two minimum density models,the minimum density model of highway separate intersection engineering is established.Based on the driver's visual physiological characteristics,this paper studies the visual behaviors of drivers when they pass the upper grade separation and overpass,analyses the adverse effects on drivers caused by billboards of upper grade separation and overpass,on the premise of ensuring traffic safety,the maximum density model of upper grade separation and overpass was established.Based on the overall advantages of the design scheme of the low embankment of the expressway,the influence of the under grade separation and passage on average fill height was analyzed.Based on the limitations of the low embankment on the under grade separation and passage density,the model of the under grade separation and passage maximum density was established.The research results of this paper are of great significance to make up for the gap of reasonable density of separate intersection engineering in China and provide certain technical support for the reasonable setting of separate intersection engineering.