Research On Comprehensive Evaluation Of The Adjustment Effect Of Expressway Guide Signs

With the rapid development of China's expressway network,the timeliness and reliability of road network information are increasingly required by road users and navigation software.After adding new roads to the original expressway network,some expressway road signs are not adjusted in time or have adjustment errors,and some road signs are not in conformity with the standards,and are selected and set in an improper position.Based on these conditions,China carried out the adjustment of traffic signs in the highway network in 2018,and unified numbering and adjustment of location and distance signs were carried out.In view of the adjustment effect,a set of evaluation index system and corresponding evaluation model were needed to support.First of all,select sample expressways for questionnaire survey and road signs investigation and analysis of the status quo.The results show that there are some problems in the setting of expressway direction signs,such as lack of useful information,unclear sign information,complex graphics and hard to understand.There are also problems such as the layout font height does not meet the requirements of the national standard,information overload of the logo layout,incomplete configuration of the warning logo and improper location setting,non-hierarchical selection of information and discontinuous selection of information.It can be seen that the direction signs need to consider whether the setting is standard,whether the information is reliable,whether the location is appropriate,whether it is convenient to understand and so on.From the perspective of the overall needs of travelers for the highway,the analysis found that the core basic requirements for safety,efficiency and comfort,and thus concluded that the requirements for road signs are standardization,readability,continuity and consistency.On this basis,a comprehensive analysis of the various factors affecting the demand for road signs,for each factor to design a quantifiable evaluation index,the index evaluation system is constructed.Based on the analysis of the meaning of the evaluation index,the method of obtaining and calculating the index value is put forward,and the method of using factor analysis to ensure the independence of each index in the index system is put forward.Considering the characteristics of the routing system and the objective of comprehensive evaluation,the TOPSIS evaluation model was selected for comprehensive evaluation,and the general operation steps and flow as well as the application of the evaluation results were put forward.Taking Hebei section of G2 expressway as an example,the application shows that the index system and evaluation model constructed are feasible and easy to operate.An evaluation value can be given for each evaluation object,and the effects before and after adjustment can be compared and analyzed according to the evaluation value.