Traffic performance on quasi-grid urban structures

Javier Ortigosa, Monica Menendez

    Research output: Contribution to journalArticle

    Abstract

    Cities across the world are starting to recover space, previously devoted to cars, for other uses. The main purpose of this paper is to better understand the removal of space in urban settings and to provide some analytical results showing that it is possible to remove streets from a city without worsening traffic excessively.We have created an abstract grid network composed of 100 nodes and bidirectional streets. A simple demand model is applied to load the network effectively, emulating a dense urban environment. We have developed a static traffic assignment model using the Frank-Wolfe algorithm. The link removal strategies seek to represent city planning policies aiming at recovering space for other activities. Links are removed following three different strategies: in a total random manner, focusing on the center of the grid, and focusing on the perimeter of the grid. Up to 30% of the total links of the full grid are removed.The results indicate that a certain number of links can be removed without affecting traffic considerably. As it will be seen, this magnitude is very dependent on the link removal strategy. Our case covers a homogeneous grid with uniform demand where the central links carry higher flow. For that, the peripheral removal allows the highest rate of link removal, whereas the central removal is the most restrictive strategy. The restriction of capacity at intersections is the main bottleneck of the system when links are removed, driving most of the increase in delays. Under these conditions, the peripheral removal retains a higher connectivity in the center, allowing a better distribution of flows.

    Original languageEnglish (US)
    Pages (from-to)18-27
    Number of pages10
    JournalCities
    Volume36
    DOIs
    StatePublished - Jan 1 2014

    Fingerprint

    urban structure
    traffic
    performance
    demand
    planning
    removal
    Urban structure
    Grid
    connectivity
    automobile
    city

    Keywords

    • Grid
    • Link removal
    • Traffic performance
    • Urban pattern

    ASJC Scopus subject areas

    • Urban Studies
    • Tourism, Leisure and Hospitality Management
    • Development
    • Sociology and Political Science

    Cite this

    Traffic performance on quasi-grid urban structures. / Ortigosa, Javier; Menendez, Monica.

    In: Cities, Vol. 36, 01.01.2014, p. 18-27.

    Research output: Contribution to journalArticle

    Ortigosa, Javier ; Menendez, Monica. / Traffic performance on quasi-grid urban structures. In: Cities. 2014 ; Vol. 36. pp. 18-27.
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