A Research On Setting Of Expressway Speed Limit Signs Appropriate Intervals Based On Drivers Cognitive Beahvior

As an important part of Chinese integrated transport systems, expressway plays an important role in shortening distance between cities and promoting regional economic development. However, the expressway brings people convenience, fast, at the same time, traffic accidents caused by "speeding" and other factors had lead to considerable negative impact. Speed limit signs are the most common way to control the speed in modern traffic management; it is also the infrastructure to guarantee traffic safety. In order to strengthen the warning of speed limit signs, it is significant to study the setting spacing between signs on expressway.This article firstly analyzed the status and problems of Chinese expressway speed limit signs setting, and researched traffic signs identification with short-term memory fading pattern and speeding impulse mechanism according to cognitive behavior theory; secendly, based on above, a experimental scenario that with traffic signs was designed by means of combination of driving simulator and questionnaire survey, and then driver's forgotten discipline and speeding impulse discipline were explored based on considering the infulencing factors such as driver's driving experience, age, sex, character, speed and road horizontal alignment etc, analyzing various factors impact on driver's short-term memory and speeding impulse; thirdly, By analyzing the collected data, drawing the curve of driver's traffic signs memory attenuating with time, a driver's short-term memory attenuation mould was build, and then the driver's speed limit signs forgotten time and speeding impulse time were consquently worked out.The conclusion shows that both the driver's forgotten time and speeding impulse time are different under different speed limits. Combined the real project application, the setting intervals were adjusted and then the follwing recommended values were concluded: expressway speed limit signs repeatedly-setting spacing value with 80km/h speed limit is 3200m,4800m for 100 km/h speed limit,6200m for 120km/h speed limit. In the end, a experimental scene with modelling tools was designed to validate the recommended values above, and the result shows that it has actual value.