对城市道路通行能力定义方法的探讨

Method to Define the Capacity of City Street Section

从理论研究和应用研究两个角度,对已有的道路通行能力的定义方法进行综述。对已有定义方法中的两个基本假设进行分析,结果表明:“瓶颈”断面受多种因素影响,不一定出现在交叉口断面;采用“瓶颈”断面表征城市道路的通行能力不具代表性,在一定的条件下甚至会高估道路的通行能力。采用道路上某一断面的通行能力作为整条道路通行能力的思想方法不适用于城市道路通行能力研究。

Firstly, a brief review of city street capacity definitions is given. By analyzing the two hypotheses of these definitions, the authors have found out that bottleneck section is affected by many kinds of disturbances and does not necessarily appear at intersection approach section, and that the capacity of the bottleneck section does not represent the street capacity, which can be overestimated in some cases. The authors conclude that the capacity of a section does can be used as the capacity of city street, even when it is the bottleneck section.