A Statistical Analysis for Capacity of Basic Expressway Sections Based on the Field Data in China

A statistical analysis for capacity of basic expressway sections was discussed based on a mass of filed data. Firstly, some basic issues of statistical analysis of capacity were discussed, which included vehicle classification, arithmetic of PCE and minimized statistical interval, because the various vehicle-types were traveling with so different performances in expressways and PCE should consider the affection of volume absolutely. Then, a two regime statistical model was provided on the basis of theoretic analysis and was established by regression analysis. Using the two regime statistical model, the serials of relationships between density-flow were obtained. Finally, some characteristics of traffic flow, such as analysis vehicle-types, recommended PCE values, minimized statistical interval, the values of recommended capacity and critical parameters, were summarized for the basic expressway sections in China.