Abstract
This study first re-examined the relationship between urban density and per capita car use which most of previous studies supported. We showed that the relationship was also interpreted as one between total urban area and total car kilometers. Next, with person trip surveys conducted in Asian and American mega-cities, the factors affecting both total urban area and total car kilometers were analyzed. We studied total urban area and total car kilometers, and their relationship with average travel speed and modal split, which were found to significantly affect these elements. Finally, we revealed that increase in average travel speed and car share contributed to the expansion of both total urban area and total car kilometers. Also, to supply efficient public transportation, in terms of travel speed, could have the effect of constraining urban area and car use.
