Traffic Operation Characteristics Analysis And Research On Risk Assessment Methods Of Sharp Curved Road Sections

In recent years,with the flourishing development of China’s roads and transportation industry,motor vehicle ownership and road mileage continues to grow rapidly,while in remote areas there are a large number of low design standards,road width is not enough,continuous curves and sharp curves more low-grade roads,vehicle driving safety cross,traffic accident rates are usually significantly higher than straight sections,but the current lack of targeted preventive measures,so in-depth understanding of sharp curves on the road traffic characteristics and trajectory,the conflict risk for its in-depth study,to improve the level of road traffic on sharp curves has important practical significance.A typical section of two-lane highway with sharp curves was selected,and firstly,based on the principle of summarizing the judgment of sharp curves,the relevant data obtained were determined to be road-related data,vehicle movement status data,traffic flow data,and vehicle characteristics data based on the purpose of the study.The survey location and survey equipment were determined,and the survey plan was established to select the appropriate survey time.The software Tracker was used to extract the raw data so as to obtain the vehicle characteristic ontology data,and the abnormal values were processed.Secondly,the overall characteristics of sharp curves were calibrated in the running direction and cross section,and the upward direction was specified as northwest to northeast,and the downward direction was northeast to southwest,and the sharp curves were divided into5 categories according to the line,and 7 categories according to the characteristic points.The overall characteristics of vehicle operation were analyzed,and the vehicles were divided into up and down directions,and the models were divided into large and small vehicles,and the five indicators of speed,angular velocity,centripetal acceleration,angular acceleration,and headway were selected to describe and statistically analyze the overall characteristics of vehicle operation.And the vehicle characteristics(speed,angular velocity,centripetal acceleration,angular acceleration,head spacing)of the sharp bend after the bend were selected for the analysis of the spatial distribution characteristics of vehicle operation.Then based on the surveyed data,the vehicle trajectories were divided into lateral and longitudinal trajectories and descriptive statistics were performed.The relevant principles of Pearson’s test were introduced,and the correlation analysis between vehicle lateral trajectories and their characteristics was carried out using Pearson’s test.Subsequently,the vehicle lateral trajectory and longitudinal trajectory of this sharp curve,as well as the vehicle lateral trajectory and vehicle characteristics were fitted using curve regression,and their correlation images were made and correlation comparisons were made.Finally,we firstly sorted out the basic theory of traffic safety evaluation,summarized the accident relationship between traffic conflicts and the commonly used methods to discriminate the occurrence of traffic conflicts,and based on the above relationship between vehicle characteristics and trajectories,we deformed the formula of time distance method,so as to carry out the risk analysis of this sharp curve,integrated the analysis of the operational risk of the sharp curve with the risk assessment index,comprehensively considered the frequency of traffic conflicts on the sharp curve section and The operational risk value of each section of the sharp curve is derived by considering the frequency and severity of traffic conflicts on the sharp curve.Some suggestions are made for the management measures and road improvement measures for the sharp bend section.