Study On The Feedbacks Between Urban Densities And Travel Mode Split

The interaction between land use and urban trips has always been one of the important research issues in the field of transportation and urban planning. The land use patterns affect travel mode choices of trip makers. Meanwhile, the changes of travel mode choices are able to make influence upon the developments of different types of urban land uses. With a feedback model developed to analyze the impacts on urban densities and travel mode split, this research explores the interactions between urban land use and travel mode choices for the sustainable development of urban transportation.Considering that a Radial Basis Function (RBF) neural network has fast self-learning ability and can effectively solve the problem of higher order interpolation, this study utilizes multiple RBF neural networks to describe the nonlinear interaction between different urban densities variables (e.g., urban rail transit network density, road network density, etc.) and the travel mode split. Accordingly, the feedback relations between different RBF neural networks are established to modeling the interactions between urban densities and travel mode split. Thereafter, the effect of different urban transportation development policies is studied with the developed feedback model. In this work, the RBF neural networks are trained by the historical statistical data of different cities in China. Under the influence of different development policies, the changes of the urban densities and travel mode split are analyzed for the built-up area of a city in the future.The analyzing results indicate that the developed model based on the RBF neural networks can rationallly explain the feedbacks between urban densities and travel mode split. In addition, as for the built-up area of the studied city, because of the feedbacks between urban densities and travel mode split, even if the urban rail network construction is greatly improved, people will still choose cars as their main travel mode when the city follow its current developing trends. At the same time, road traffic will face up to enormous pressure and a large number of rail transportation resources will be wasted. When decelerating the expansion of the urban area of the city and slowing down its road construction without exactly increasing the utilization of urban rail tranits, trips with private cars will still make a big pressure on the urban road traffics, even if private car uses are limited. In comparison, making more private car users and the public transport passengers take urban rail transits is the effective way to rationalize the travel mode split.