Analysis And Evaluation Of The Effect On Traffic Safety Of Trunk Highway Alignment

Arterial highway refers to the national highway and provincial highway, which are the important components of highway network of our country, and play a decisive role in the national economy. Road traffic system is a dynamic system which consists of people, vehicles and roads. Highway alignment as part of the most basic elements of the highway, play a decisive role in this system, highway design personnel must pay attention to the road alignment factors impact on traffic safety.With the increasingly traffic volume, the safety issues of the traffic of the arterial highway become prominent gradually. In order to reduce traffic accidents and lower the level of severity of accidents. This paper emphasizes on analyzing the linear factors in the road condition, explains the relationship between the linear factors and the traffic safety in detail and starts the objective evaluation on arterial highway safety with the linear factors, embodying a very important guidance function to prevent the traffic accidents hindering the traffic of the arterial highway.This paper introduces in detail three evaluation methods of the linear safety of arterial highway based on the analysis of the influencing factors of safety of the traffic of the arterial highway: evaluation method of speed consistency, safety evaluation method about geometric linear design and cornering ratio evaluation method. This paper also establishes index weight by means of analytic hierarchy process and puts forward the models of evaluation indicators in evaluation method and the range of marks graded. It gives specific scores to single evaluation index by means of comprehensive evaluation and builds the comprehensive evaluation model of the linear safety of arterial highway. Compared three evaluation results with the comprehensive evaluation result by doing safety evaluation on the K55+105~K65+890 section of the highway from Zhenning to Shuicheng in Guizhou province, explained the reason of the performance difference between single evaluation method and comprehensive evaluation method, and verified the applicability and reliability of the constructed comprehensive model and the comprehensive method in this paper.The safety evaluation method of the road alignment and the comprehensive evaluation model of the linear safety play the supporting and reference roles when the road designers are conducting the linear design, which can and even eliminate the hidden dangers during the road's operational phase, ensuring the safety and stability of the traffic vehicles.