Rajesh Gopinath, Deepak D.G


'Aspect Ratio', a commonly used indicator to describe typical urban geometry is computed as the average ratio of the building heights ‘H’ to the canyon width 'W'. Its determination techniques in the present urbanization scenario is bound by certain assumptions which falter as most cities across globe does not project a well-planned street profile. An urban canyon factor is of most significance in climatic and air quality studies.
The study showcases how the standard assumptions cited in literatures for Urban Morphological Analysis cannot apply to most urban canyons in any townships that have evolved rampantly. The present research recommends a rationally feasible methodology of analytically ascertaining and representing Aspect Ratio for variant street canyons. The research objective envisaged selection of 3 random locations encompassing heterogeneous street canyon geometries. At each of these locations its land-use pattern and road network was mapped for a radius of 250m by supervised-classification to assist in extracting the canyon geometry features, namely building height and road width across all the streets.
The revised methodology judiciously delves upon when stations also have plots without pre-defined boundaries for creation of layouts. The logic encompasses complete dimensional analysis, and accounts for all four directions, the dynamic road width and building length measured along street about each focal point. The present research recommends this technique for a study of any magnitude; and encompassing just a street or even an entire city; as it’s practically applicable to any site condition and does away with errors due to the ‘idealistic’ assumptions.


Aspect, canyon, dimensional, elevation, ratio, urban

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DOI: https://doi.org/10.23968/2500-0055-2017-2-3-11-20


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