出行时耗预算机理解析

从20世纪60年代开始，一些学者发现城市居民人均日出行时耗在不同年份表现出一定的稳定性；扎·哈维提出日平均出行时耗预算相对恒定假设。首先，通过国内外全日、单次出行平均时耗变化的历史数据，验证了出行时耗的相对稳定性。在解析出行时耗相对恒定形成机理的基础上，重点分析单次通勤出行时耗分布机理，并提出相应的模拟公式。同时，探讨交通拥堵状况对出行时耗分布的影响作用，分析表明较小的出行时耗增加可能隐含较大程度的交通拥堵。最后指出，应结合中国城市居民的出行时耗预算，为其适宜的交通模式规划路网和城市用地布局。

Discussion on Travel Time Budget

Starting 1960s, scholars have found that the average daily travel time of urban residents tends to be stable in different years. Y. Zahavi developed a hypothesis that daily travel time budget is relatively con-stant. Through the data analysis of daily travel time and single-trip travel time both at home and abroad, this paper proves the relative stability of travel time assumption. Based on the analysis of mechanism of rel-ative stable travel time, the paper focuses on the distribution of single commuting travel time and proposes the simulation formula accordingly. By discussing the impact of traffic congestion on travel time distribu-tion, the paper reveals that a small travel time increase can result in severe traffic congestion. Finally, the paper points out that roadway network and urban land use plan should consider Chinese residents’travel time budget and travel modes.