Research On Traffic Flow Characteristics And Safety Guarantee Technology Of Crossing Urban Roads

Road traffic is an active factor in social activities and can promote regional economic development.Therefore,many transit highways merge with urban trunk roads.Transit highways must meet both transit traffic and the travel requirements of urban residents.Such transit highways are called crossing urban roads.The research on the safety protection technology of urban road traffic is conducive to ensuring driving safety and comfort and improving road traffic safety.First,the definition of crossing urban roads is proposed.The road is divided into highway section,adaptation section and urban section.Analyze the characteristics of roads passing through towns,analyze road risk factors from the perspective of people,cars,roads,and the environment,and analyze the accidents of roads passing through towns from the perspective of accident patterns and time distribution.Secondly,through the test data,the vehicle speed,headway and driver heart rate growth rate of each road section are analyzed.Explore the relationship between the rate of change of speed and the rate of increase of heart rate at intersections.The 17 fixation points of the driver are divided into 7 categories,and the fixation time,glance angle,and scan rate of different types of fixation points on each road section are analyzed.The threshold for getting the driver’s gaze time is 134.29 ms-449.07 ms.Combining gaze and saccade indicators,a driver distraction index is proposed.Then,based on the characteristics of crossing urban roads,establish a safety evaluation index system from five aspects: "driver","speed characteristics","traffic composition","road conditions" and "traffic environment".Compare and analyze the existing traffic safety evaluation methods,combining matter-element extension method and cloud model to build an extension cloud model for road traffic safety evaluation through cities and towns.Finally,based on the theory of speed consistency,the rationality of the speed of vehicles on each section of the urban road is analyzed.Arrange intermittent deceleration belts on sections with poor speed consistency.According to the principle of maximum entropy,the reasonable distance between intersections is determined to be 600-750 m,and the corresponding safety measures for intersections are proposed.The research results can not only improve the connection between sections of urban roads,but also improve road safety.