Prior Evaluation Method Of Traffic Safety For Highway Based On Speed Forecasting

Highway is an important part of transportation system, and traffic safety problem is becoming more and more prominent with the rapid growth of highway mileage. Traffic safety evaluation for highway is the foundation of ensuring highway operating safety, and it’s of great significance to reduce traffic accidents and improve transport efficiency.Based on the distribution characteristics of highway traffic accidents and the safety analysis of different traffic flow states, a prior evaluation method of highway traffic safety based on speed forcasting is proposed. At the same time, the evaluation period is shorten in order to evaluate the highway traffic safety level before accidents happen and make dynamic earlywarning of driving risk to take preventive measures in advance.Firstly, considering the advantages and disadvantages of neural network model and the fuzzy inference system, the adaptive-network-based fuzzy inference system (ANFIS) is applied to highway speed short-time forecasting. Combined with the significant analysis of affecting factors of speed, traffic volume, visibility and rainfall intensity are added as additional forecasting factors. Then a highway speed short-time forecasting model based on ANFIS is constructed after selecting appropriate model parameters.Secondly, speed discreteness, continuity, coordination and weather conditions are considered to build the highway traffic safety evaluation indexes system based on speedforecasting. AHP is used to calculate the weight coefficients of evaluation indexes and the calculation method of correlation function is improved, and then the improved matter-element analysis method is applied to highway traffic safety evaluation.Finally, taking the segments in Hubei Province of Beijing-HK-Macao highway as example, the highway speed short-time forecasting model based on ANFIS is applied to calculate the evaluation indexes, and then traffic safety of Xian’an to Xianning segment is evaluated with the improved matter-element analysis method, the result shows that the prior evaluation method of traffic safety for highway based on speed forecasting is feasible and rational.