Optimization Of Road Warning Signs System Based On The Accident Risk Analysis

At present,the situation of road traffic safety in China is not very optimistic,and traffic accident rate increased year by year.As the illustration of highway,traffic signs play a very important role.However,the poor overall coordination of traffic signs' design and setting make drivers feel confused and heavy burden which produce unsafe risk.Therefore improving the level of traffic signs setting is of great significance to guarantee the usage efficiency and highway safety.Existing research on the traffic signs mainly focus on the individual technical parameters rather than considering the entire road network of the macro signs setting. This paper regarded the warning signs as study object.From the view of the road network,through the analysis of drivers' perception psychology and behavioral characteristics,bring forward a travel utility model based on the time cost and accident risk loss.Use the theoretical of cognitive psychology,ergonomics and economics to analyze the drivers' perception characteristics with the risk on road section and divided cognitive behaviors into objective and subjective perception so as to be quantified. Based on quantitative results,integrated cognitive model of drivers can be proposed. Finally the optimal methods of warning signs are identified.This method adopted fuzzy comprehensive evaluation method to assess the objective accident risk of observed section by dint of the actual observation data.Then applying the quantitative results of risk perception to the optimal model of warning signs,introducing PSO to solve model and using VC++ to implement.At last the proposed model was verified by the optimal results of warning signs setting on 312 State Road secondary road in Xi'an.This study, not only focused on the detail research of effects of warning signs in road network and road section,but also briefly introduced the method of calculating advanced distance for individual,thus realized the level optimization from single to road section,then to road network.The purpose of study is to provide reference for traffic management department about improving the existing warning signs,and then the management and service function of traffic signs can be better brought into play.