Study On Prediction Model Of Highway Operation Speed After Reconstruction

Along with the development of the national economy,the highway in our country,as the second only to the expressway,also develops rapidly and the mileage of the road rises steadily.And its prosperity and development bring many problems.In addition to the high cost of a highway,large area and other unfavorable factors,a highway also has many traffic safety issues like the highway.The linear design indicators are generally high,the main line speed is generally faster,flat cross-mouth,incomplete closure caused by frequent access,serious horizontal interference,the speed of the vehicle to grasp the characteristics of inaccurate and so on are the main cause of a variety of security issues the reason.This will lead to the improper setting of road facilities,the uncoordination of road sections,the restriction of speed and speed,and the inconsistent operation speed,which bring serious potential safety hazards to the operation of roads.Therefore,this paper aims at a variety of road line appeared in the first class highway,and considering the different factors that affect the running speed,the establishment of the operating speed prediction model to provide assistance for road traffic safety assessment.This paper selects Tangshan-Caofeidian Class I highway as the research object.According to the research purpose,it is necessary to carry out relevant surveys in different characteristic sections.Therefore,two representative intersections and several characteristic sections are selected for data collection in Tang Cao Road.In the course of the investigation,many key sections were also surveyed,such as different road line connections,intersection deceleration zones and so on.The survey aims to investigate the characteristics of vehicles running speed at the characteristic road sections and at the entrance / exit intersections under the current conditions and grasp the characteristics of the running speed of the vehicles in the characteristic sections,the technical indexes of the characteristic sections and the factors influencing the operation speed.The main conclusions of the survey can be used as a reference for the new line speed management,but also can be used as the basis for the speed management of the construction section of the characteristic sections.In the course of establishing the running speed prediction model,the influence of the combination of straight line,flat curve,longitudinal slope and curved slope on the running speed is analyzed first,and then the prediction model is established for each kind of line type in the most extent,The road conditions appearing in the highway improve the effectiveness of the model.In order to verify the accuracy of the forecasting model,this paper selects the Liangping-Wanzhou Expressway to predict the velocity and the velocity of the characteristic points.Prediction of operating speed and the actual operating speed trends are basically the same,ruled out the driver’s abnormal driving behavior,the curve radius is smaller,the slope of the road line type,the prediction model has a higher accuracy,good practical value,for the transport road Safety evaluation to provide guidance.According to the actual operation of Tang Cao Highway and other first-class highways,this dissertation analyzes the roadside disturbance and exit density as two important aspects that affect the accuracy of the running speed model.Therefore,the model is modified according to the mechanism that two factors affect the running speed,and then a more accurate and practical running speed prediction model is obtained.Through the calculation and analysis of the operation speed of different linear sections by the prediction model,it is found that the safety of some roads or sections is low.It is suggested that the speed control should be carried out in the dangerous position,and the deceleration control scheme should be put forward.