Study On The Optimization Method Of Rumble Strips On The Mountain Freeway

The analysis of traffic incidents statistics shows that speeding behavior of vehicles is one of the chief causes of traffic accident. The more complicated traffic environment and less monitoring facilities of mountain freeway has caused frequent speeding phenomena easily, which leads to security risks. To ensure the safe and stable operation of the mountain freeway, some speed control facilities should be taken into practice to prevent from high-frequent speeding behavior and reduce the vehicles’ speed. And the rumble strips have quickly became one of the most widely-used speed control facilities since their gentle force and good slowing effects. However, China lacks of specialized and systematic setting specifics for the rumble strips at present, and the research results of rumble strips’ setting methods are almost base on the deceleration effectiveness and ignoring the drivers’ factor which is one of the most important factors of traffic system. Therefore, a complete and systematic research on the setting methods of rumble strips would be necessary which considering the special traffic conditions of mountain freeway, the vehicle movement and drivers’ characteristics. And it is of great significance for the optimization design of rumble strips which may effectively reduce the traffic accidents caused by speeding phenomena and promote the active defense ability of mountain freeway.Given these, this paper studies the rumble strips of different repeated strips and locations. Firstly, introduce the types and main key parameters of rumble strips, and analyze the deceleration mechanism which based on the proposed drivers’ information processing model of rumble strips. Secondly, a questionnaire was used to study the drivers’ recognition degree of rumble strips, the characteristics of decelerating behavior, etc. Also the data about vehicle movement state and drivers’ characteristics was gathered through road tests. Next, speed, acceleration, acceleration noise and speed droop are chosen as the indicators which represent the vehicle movement state, then analyze their changes and significant differences. Then, acceleration and deceleration behavior choice, the recognition distance of rumble strips and the growth of heart rate are chosen as the parameters which indicate drivers’ characteristics, then analyze their changes and significant differences. Meanwhile, two models were established to forecast the recognition distance and the growth of heart rate. Finally, the optimization concept of rumble strips is proposed which based on the principles of speed slowing effect, recognition security and driver comfort. In this way, the optimization methods are discussed according to the results of the questionnaire and the experiments.The research results of this article would provide advices for the optimization design of rumble strips, also have positive effects on decreasing the speeding phenomena and promoting the traffic security of mountain freeway.