City logistics long-term planning: simulation of shopping mobility and goods restocking and related support systems

The growing necessity to improve city sustainability and liveability has pushed local administrators to look also at medium/long-term city logistics measures, such as land-use governance policies. In order to assess long-term scenarios, it is necessary to have models and methods able to take into account the effects on shopping mobility and goods restocking, generated by these classes of measures (e.g. relocation of shopping zones). Besides, we have to consider that modifications of shopping attitudes, deriving from changes of demographic and socio-economic characteristics of end consumers, can impact on purchasing behaviour and hence on restocking mobility. This paper discusses a number of issues related to the simulation of medium/long-term scenarios and presents a system of models that consider shopping mobility and restocking jointly. The presented shopping demand models, in combination with urban restocking models, are implemented within a simulation support system named City Logistics Analysis and Simulation Support System and are used to assess the effects on the freight restocking due to demographic and socio-economic variations including some hypotheses on new land-use development governance measures in a medium-size urban area. The main results confirm the modelling goodness and, at the same time, demonstrate that changes in demographic and socio-economic characteristics could cause relevant effects, in particular increasing car use in shopping mobility. The growing e-shopping could limit the negative effects of these changes, but the impacts of home deliveries have to be considered. The relocation of commercial and logistics centres, closer to the residential distribution, could drive a different restocking pattern with a consequent reduction in freight vehicle mobility. Anyway, this reduction is not very relevant and therefore further city logistics measures have to be implemented.