Accessibility Change of Automobile Traffic in the Tohoku District

Abstract

It is necessary for regional planning to understand the regional structure correctly. Accessibility has been used as one of the measures for understanding the regional structure. Actual phenomena are consisted of various factors complicatedly, and as times went by, their structures come to be changed, thus a choice and a combination of attributes and parameters in formulas of the models are important to measure accessibility. Therefore, in this paper, the new potential accessibility model using the values of some distance frictions with considering quality of road linkages is established to understand automobile flow structures. The purposes of this paper are to calculate automobile traffic accessibility which changes since 1971 to 1994 in the Tohoku district, and to find which regional attributes give an impact on the accessibility of the city. The accessibility changes are measured by using the new potential accessibility model, and the multiple regression analysis is employed to search the regional attributes which give an impact on the accessibility changes. The data used are the Automobile O-D Survey conducted by the Ministry of Construction during the each autumn of 1971 and 1994. The main findings are summarized as follows : 1. As the the percentage of shortening of time distance by using express ways increases as the values of distance friction of automobiles decrease. Thus considering the quality of linkages is necessary to measure accessibility by using the method of potential measure. 2. Since 1971 to 1994, the value of distance friction of passenger cars increased from 3.211 to 3.501 because of the acceleration of motorization. On the other hand, that of freight cars decreased from 3.124 to 2.830 because of the extension of highway network. 3. The mean percentage which potential accessibility of passenger cars grew since 1971 to 1994 in the Tohoku district is 144.4, and that of freight cars is 1,387.6. 4. DID (Densely Inhabited District) population in the regional attributes give an impact on the accessibility of passenger cars ; in the same way, the economic attributes, including annual sum of retail selling, give an impact on the accessibility of freight cars.