Quantitative approaches for walking accessibility of metro stations

In China, many metropolises (such as Beijing, Shanghai, Guangzhou, Wuhan) are developing metro railway systems to relieve traffic jam. Due to lack of quantitative analysis tools for comparison of different options, planners have to make decision for metro station locations mainly based on their experiences and qualitative approaches which are considered unreliable to a certain extent. Therefore, we present a number of quantitative methods and measures based on GIS in this research. A case study has been conducted in Wuhan to test the effectiveness of these methods and quantitative measures. Luxiang Roundabout area in Wuhan where six major roads intersect, is inflicted with heavy traffic jam. To reduce the traffic volume, Guanggu metro station has been under construction nearby. We implement three methods to determine the service area of Guanggu metro station: buffer analysis, network analysis and Cost Distance analysis. After comparison, Cost Distance analysis is proven to be a more accurate and reliable way to analyze walking accessibility and service area of a metro station. Then, we measure and compare the amount of accessible area, building footprint area, building floor space within different walking time to the metro station under construction and a possible alternative location with station located in the center of the roundabout. The latter one offers a better choice in terms of walking accessibility.