14. Quantitative Assessment of Urban Road Network Hierarchy, Topology, and Walkable Access Using Open-Source GIS Tools

To support the road transportation system and improve the performance of vehicular traffic movement, the efficacy of the road networks is of utmost importance. This paper highlights a quantitative analysis of urban road network hierarchy, topology, and pedestrian accessibility by utilizing free and open-source GIS tools and OpenStreetMap (OSM). The topological pattern of the road network was assessed in terms of connectivity and coverage measures using graph theory. The study area was analyzed by computing selected topological measures across several square grids at varying scales. The results showed that the size of the grid influences the numerical values of topological measures differently. Two other measures such as AwaP (area-weighted average perimeter) and IC (interface catchment) were also explored to study walkable accessibility that enabled analysis of actual urban morphologies based on OSM urban footprint. Further, a hierarchy of road and street networks was generated using COINS (Continuity In Street Networks) and the results indicated that this algorithm could detect the skeletal structure of a city’s road network. The study suggested that improving road networks in underdeveloped regions could promote urban development and economic growth.