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Research on the Method of Dynamic Speed Limit on Expressway under Complex Climate Based on Pavement Skid-Resistant Performance

To solve the problems in the current deterministic method of a maximum speed limit for expressway, a method of dynamic speed limit on expressway under complex climate was presented which was based on pavement skid-resistant performance. Firstly, the variation of pavement skid-resistant performance under complex climate conditions was analysed based on research results and certain experimental statistic data. By analysing the influence rule of AC-16 and SMA-16 pavement texture, pavement temperature, water film thickness, ice thickness, vehicle speed to pavement Skid-Resistant Performance, pavement actual friction coefficient calculation model and reference standard were established under different pavement condition Then, by analysing the geometry line indexes, pavement conditions and vehicle dynamics, the critical sideslip speed and critical longitudinal-driving safety speed was formulated; therefore, with critical speed as a constraint of safety driving and interval classification of complex climatic conditions, the dynamic speed calculate method and safety speed control standard were proposed under various pavements conditions, visibilities and traffic environments. This method for overcoming the weakness of a maximum speed limit of expressway operation and improving traffic safety is helpful.