The Layout Information Threshold And Density Of Traffic Signs On Urban Arterials

City road traffic signs are the indispensable parts of the transportation system.Reasonable traffic sign designs and settings can provide traffic participants with road conditions information and guide them drive safely.So far,there is no uniform design standard for the layout information and density of traffic signs in China,which results in the overloading of many traffic signboards.This paper adopted after effects video software and E-Prime psychology software to simulate the process of traffic signs from far to near.On the basis,the study tested the average response time and response correct rate of the subject’s search for target road names.The results showed that the average response time of the driver was positively related to the amount of layout information items on the traffic signs,and the accuracy of the response was negatively related to the number of layout information items.There were significant differences between the groups when the amount of information was increased from seven to eight.Therefore,the information threshold was seven.Then,according to the different information types,the common traffic signs on urban arterial roads were divided into eight categories.Experiments got the average reaction time and the conversion factors of different types of traffic signs,so as to obtain unified calculation method of traffic signs information on road sections.The density threshold was thirty-eight unit value per kilometer obtained with traffic density threshold experiment.Finally,a field survey was conducted on the setting of traffic signs on the Jinniu avenue,which is the main road of Chengdu.The density of adjacent traffic signs was calculated and compared with the density threshold.And the study gave the recommended spacing for setting traffic signs.