Research On Safety Evaluation Of Truck Driving On Expressway Based On G42 Data

With China becoming the world’s largest highway cargo transportation market,expressway freight transportation has become an indispensable part.However,with the large traffic flow and overloading development of expressway freight transportation,the safety of expressway truck driving has been greatly challenged.Based on this status quo,this paper effectively explores the potential influencing factors and influence law of expressway truck accidents and builds safety evaluation models for expressway truck driving.Using these models to find high-risk sections and conditions of freeway truck driving in time,and propose effective and targeted safety improvements to achieve the goal of improving the overall safety level of the expressway.Based on the historical truck accident data of expressway,this paper explores the states,time and spatial distribution characteristics of expressway truck accidents and the direct causes of them,and analyzes the driving characteristics of trucks from the perspectives of truck operating speed and truck driving state impact effects.Then this paper starts from three aspects of road environment factors,expressway entrance and exit area factors and traffic flow statu factors to quantitatively analyzes the relationship between each impact factor and truck accident rate,and explores how these factors affect the risk of freeway truck driving.After the overall understanding of the impact factors of highway truck driving safety,this paper constructs two evaluation models of expressway truck driving safety from aspects of expressway entrance and exit area factors and traffic flow state factors.The brief description of the two models is as following:(1)A Bayesian network model with multiple node variables including factors in the freeway entrance and exit area and the number of truck accidents is constructed by using Matlab software to learn network structure and parameters based on Bayesian network principle,and prove the accuracy of the model by testing the remaining sample data.This model can be used to analyzes the safety level of trucks in highways with multiple or single factor variables.The model results show that the trucks have the worst driving safety in the range of 0～500m upstream of the expressway exit nose;(2)Through VISSIM simulation software,a simulated model is built based on the actual situation of the research object expressway G42,and the validity of the output results of the model is verified and proved.Then,the model is used to output speed evaluation data under various traffic flow conditions.After the relationship between the trunk accident rate per 100 million vehicle kilometers and the speed coefficient of variation is fitted by using historical truck accident data and traffic flow data,the speed coefficient of variation is taken as an index for evaluating the safety of truck driving,and a regression model between the speed coefficient of variation and various factors of traffic flow is built.With this model,the safety of truck driving under various traffic flow conditions could be evaluated,and the results of the model show that the factors of "traffic volume" and "the proportion of traffic drive off the main line" are the strongest correlation with the safety level of trucks driving and is positively correlated with the evaluation index speed coefficient of variation.At the end of this paper,two models are applied to evaluate the example expressway sections to prove the effectiveness of the model and propose corresponding safety improvement countermeasures.90 figures,57 tables,74 references.