| Summary: | Since the last quarter of the twentieth century, the rapid growth in many cities
throughout the world was the predominant cause of the phenomenon of urban sprawl.
In this backdrop, The over-expanded urban spaces let to intensify the negative impact
of the high solar radiation in the hot climate regions that caused abandoned pedestrian
zones. There is a growing body of literature highlighted the compacted urban spaces
as the most prioritized approach against urban sprawl and high solar radiation. The
compacted pedestrian zones reduce the overexpansion and mitigate solar radiation by
promoting mutual shading. Meanwhile, controlling the morphology of the pedestrian
zone have been identified as an essential contributing factor to improve shading and
limitate the overexpansion. The morphology of the pedestrian zone was described by
three parameters proportions, orientation, and vegetation. These descriptors are
characterized by being variable within the urban fabric, resulting in a difference in the
shading efficiency in the pedestrian zones. Besides, the shading requirements toward
pedestrian also vary since the shading is a dynamic physical phenomenon that changes
in daily and seasonally basis to a specific geographic location. Hence, the variability
of the morphology descriptors and shading requirements have made controlling the
over-expansion in the pedestrian zone a complicated issue. Therefore, the majority of
the studies have utilized computer simulation using different shading assessment
software and tools. Although the shading can be calculated using these software and
tools at a high level of accuracy; however, they are considered as an analytical tool.
The available software and shading assessment tools did not provide regulatory constraints to control the overexpansion pedestrian zone to an effective limit that keeps
shading feasible for the pedestrian. Hence, there is an uncertainty of providing a
tangible policy to improve shading in the pedestrian zones. Consequently, in this study,
a prediction tool was developed to set regulatory constraints by identifying the
expansion limit corresponding to the targeted shading efficiency. The shading
efficiency represented the percentage of the shaded area to the total floor area of the
pedestrian zone, while the targeted shading efficiency indicated the preferable shading
requirements for the pedestrian. The development of the prediction tool was conducted
base on integrating three sequenced algorithms, which are sun position algorithm,
shadow length and position algorithm, and expansion limit algorithm. Then the
developed prediction tool was tested in the Muscat coordinates. The study concluded
that the shading performance in the pedestrian zone was due to a combination of
effective morphology configuration within a particular expansion limit. Moreover, the
study provided systematic solutions based on reconfiguring the pedestrian zone by the
trees. The trees can behave as an environmental modifier to maintain the shading of
the pedestrian zone within an acceptable level.
Then ECOTECT software has utilized to validate the effectiveness of the
developed prediction tool for evaluating and improving the shading efficiency in the
pedestrian zone. The ECOTECT has been selected because of its capabilities that allow
the user to simulate and compare the shadow casting ability for both unshaded and
shaded scenarios. The results of ECOTECT simulation validated the effectiveness of
the prediction tool to provide regulatory constraints to evaluate and improve the
shading efficiency of the pedestrian zone.
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