Development and Comparison of Freight Distribution Models of Inland Water Transport along Yangtze River Economic Belt with Ship Visa Data

The Yangtze River Economic Belt (YREB) serves as the main east-west axis of the economic development of China. Studying the characteristics of the Yangtze River on waterway freight transportation plays a significant role in propelling the development of the Yangtze River transport network and releasing the transport potential of the Yangtze River. In this study, the data of ship visa in 2010 were used to conduct the OD matrices of different freight types. Then, freight desire lines of the YREB were drawn in TransCAD according to the OD matrices acquired. In addition, the freight relations and characteristics of each port and three economic circles in the YREB were analyzed. After that, this paper applies the freight distribution models such as gravity distribution models and the intervening opportunity models to analyze the distribution of coal and its products, steel and nonferrous metals respectively. In particular, the impedance function of the gravity distribution model include the inverse power function, the exponential function and the gamma function, then their parameters were calibrated. Finally, the value of Average Trip Length (ATL) and Trip Length Frequency Distribution (TLFD) were measured and compared with the value calculated, then the results indicated that the gravity distribution model based on an inverse power function was higher than the Intervening Opportunity (IO) models in the coincidence ratio, and the freight distribution matches this in the reality.