Eliminating Overload Trucking via a Modal Shift to Achieve Intercity Freight Sustainability: A System Dynamics Approach

The Chinese government has long been preoccupied with solving the problem of overloaded trucking in intercity freight systems (IFSs). The enforcement of prohibiting overloaded trucking, which enhances environmental and social performance of sustainability, has not progressed well, as it raises transport costs and lowers economic performance, and cannot improve the overall performance of sustainability. It is, thus, necessary to find a way to eliminate overloaded trucking without undermining the overall performance of sustainability. A modal shift is a potential way to achieve freight sustainability, by encouraging greater use of more efficient transport modes. This paper develops a system dynamics model to perform a long-term evaluation of alternative modal shift policies with trucks meeting the statutory limit, and then identified effective policies, whereby the increasing sustainability of IFSs could be achieved. The proposed model was applied to a specific case in China. The results show that the effective modal shift policy is to construct a Class I railway to shift freight away from highways. A discussion is then proposed, based on an analysis of different parameter setting scenarios regarding more general situations.