Rethinking road network hierarchy towards new accessibility perspectives

Abstract

Conventional road network hierarchy has focused mainly on facilitating car movement, while (usually) neglecting the rest surface transport modes. This fact resulted in dysfunctional urban environments where a plethora of social, economic and environmental issues are encountered. In this context, serious inequalities regarding urban mobility arise (e.g., inaccessible areas without car, exclusion of vulnerable social groups from a fair transport system, etc.). Therefore, there is an urgent need to bring forth the notion of accessibility and the fair access to opportunities, in transport systems and specifically in road network hierarchy.This study aspires to explore whether the rethinking/reformulating of the road network hierarchy can improve the accessibility level for sustainable modes (public transport and cycling/micromobility) in different transport future paths. To this end, 4 different scenarios that redefine the strategic road network of the study area are developed: 1) Business as Usual (BAU), 2) Car-oriented city, 3) Public Transport Priority, 4) Sustainable Modes Integration. Next, a combinatorial approach evaluating these scenarios is adopted: specifically, the spatial accessibility concerning cars, public transport and cycling/micromobility in each scenario is estimated. This method is applied to the metropolitan area of Athens, Greece which can be considered as a challenging example of a car-oriented metropolis. The main results indicate that the fourth scenario integrating all sustainable modes can improve the accessibility of public transport and cycling, while restraining car dominance in terms of access to opportunities. These findings are particularly useful for researchers and practitioners and could be taken into account for the making of human-oriented cities with a better level of mobility for all in the future.