Measuring accessibility and congestion in Accra

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningfagfællebedømt

Based on extensive gps-measurements, the paper addresses the level of intra-urban accessibility and provides indications of the level of congestion in Accra, Ghana. Traffic flows within the urban area are analyzed with respect to speed, time-of-day, direction, road type and land cover type. The speed information is extrapolated to cover the total mapped urban road net¬work with time- and direction-specific data. A series of time-distance maps are created using network analysis to illustrate the level of accessibility at different times of the day and at different directions relative to the city centre. Peak hour traffic speeds are compared with off-peak levels and theoretical free-flow estimations to provide an indica-tion of the level of congestion. It is found that the core areas are somewhat congested during the day period, while the fringe areas are more congested during peak hours and less during off-peak hours. Delays are frequently found within the inner fringe areas. The paper discusses the methodological potentials and barriers for applying gps tracklog points for analysing traffic flows within an urban road network.
OriginalsprogEngelsk
TidsskriftNorsk Geografisk Tidsskrift
Vol/bind66
Udgave nummer1
Sider (fra-til)52-60
Antal sider9
ISSN0029-1951
DOI
StatusUdgivet - 2012

ID: 37755087