2018 Volume 5 Pages 1-24
This paper calculates the optimal urban form for a given total floor area with minimization of the total travel cost and studies the impact of changing various factors, by assuming the presence of multiple floors in three-dimensional cities having a hierarchical space structure. In this paper the optimal urban form is defined as the urban form offering the minimum travel cost, from an arbitrary point in a city to a specific city center site. For vertical transfers, a model is formulated by assuming the presence of multiple floors. This assumption makes the model more realistic and closer to actual cities than conventional models where multiple floors are disregarded. The results show that the optimal urban form changed; retaining similarity when the total floor area was changed, but without doing so when the vertical travel cost or travel cost by short-distance transportation changed. The paper also compares the city model and an actual city form to clarify the difference. The optimal urban form derived from the model calculation has a far smaller horizontal size than the actual city and hence includes many high-rise buildings, which differs significantly from the form of the actual city. Consequently, the optimal urban form with respect to the travel cost was that in which ultra high-rise buildings were concentrated in the city center.
