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Developing a prediction tool to improve the shading efficiency of the pedestrian zones / Wael A. Khudhayer

Developing a prediction tool to improve the shading efficiency of the pedestrian zones_Wael A. Khudhayer_A9_2020_MYMY
Semenjak suku abad ke dua puluh, arus perkembangan pembangunan dalam bandar-bandar seantero dunia telah menjadi penyebab dominan kepada fenomena rebakan bandar. Dalam latar belakang ini, ruang-ruang perbandaran yang berkembang secara melampau telah mempergiatkan lagi impak negatif radiasi solar yang tinggi dalam wilayah-wilayah beriklim panas yang secara tidak langsung menyebabkan zon pejalan kaki diabaikan. Terdapat perkembangan dalam literasi yang menggariskan bahawa ruang perbandaran yang mampat adalah pendekatan yang paling diutamakan yang menyebabkan rebakan bandar dan radiasi solar yang tinggi. Zon pejalan kaki yang mampat dapat mengurangkan pengembangan melampau dan mencegah radiasi solar dengan menggalakkan teduhan sepunya. Sementara itu, pengawalan morfologi terhadap zon pejalan kaki telah dikenalpasti sebagai penyumbang faktor utama untuk menaiktaraf teduhan dan mengehadkan pengembangan melampau. Morfologi zon pejalan kaki dijelaskan dengan tiga parameter; perkadaran, orientasi dan vegetasi. Parameter-parameter ini telah dicirikan oleh pemboleh ubah dalam fabrik bandar seterusnya menghasilkan perbezaan kecekapan teduhan di zon pejalan kaki. Selain itu, syarat-syarat teduhan terhadap pejalan kaki adalah berbeza disebabkan teduhan mempunyai sifat fizikal yang dinamik yang berubah mengikut hari dan musim, bergantung kepada spesifikasi lokasi geografi. Justeru, variasi dalam morfologi parameter dan keperluan teduhan telah menyebabkan pengawalan terhadap pengembangan melampau dalam zon pejalan kaki menjadi isu yang rumit. Oleh itu, majoriti kajian telah menggunakan simulasi yang menggunakan perisian-perisian penilaian teduhan yang berbeza. Walaupun teduhan tersebut boleh dikira dengan tepat menggunakan perisian-perisian ini, namun perisian-perisian ini hanya boleh dianggap sebagai alat analisis. Perisian dan alat analisis yang sedia ada tidak menyediakan peraturan kekangan pengawalan pengembangan melampau terhadap zon pejalan kaki sehingga limit yang efektif untuk mengekalkan teduhan tersebut sebagai mesra pengguna. Oleh itu, terdapat keraguan dalam penyediaan dasar khas untuk menaiktaraf teduhan di kawasan pejalan kaki. Kesannya, kajian ini telah menghasilkan alat ramalan untuk menetapkan garis panduan terhadap kekangan dengan mengenalpasti had pengembangan yang sepadan dengan tahap kecekapan teduhan yang disasarkan. Tahap kecekapan teduhan mewakili peratusan kawasan teduhan kepada jumlah keseluruhan ruang lantai zon pejalan kaki sementara itu, tahap kecekapan teduhan merujuk kepada syarat-syarat teduhan yang lebih baik kepada pejalan kaki. Alat ramalan ini dihasilkan berdasarkan tiga algoritma bersepadu iaitu algoritma kedudukan matahari, algoritma dan panjang bayang serta algoritma had pengembangan. Seterusnya, alat ramalan ini diuji di kawasan Muscat, Oman Kajian ini menghasilkan kesimpulan bahawa prestasi teduhan di zon pejalan kaki bergantung kepada kombinasi konfigurasi morfologi yang efektif dalam had pengembangan yang tertentu. Tambahan pula, kajian ini menyediakan penyelesaian yang sistematik berdasarkan penyusunan semula konfigurasi zon pejalan kaki dengan merujuk kepada pokok-pokok. Pokok-pokok boleh bertindak sebagai pengubah alam sekitar dalam mengekalkan teduhan di zon pejalan kaki kepada tahap yang boleh diterima. Keputusan daripada simulasi ECOTECT telah mengesahkan keberkesanan alat ramalan ini untuk menghasilkan garis panduan terhadap kekangan yang menilai dan menaiktaraf kecekapan teduhan di zon pejalan kaki. _____________________________________________________________________ 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
Contributor(s):
Wael A. Khudhayer - Author
Primary Item Type:
Thesis
Identifiers:
Accession Number : 875008826
Language:
English
Subject Keywords:
twentieth; prioritized; morphology
Sponsor - Description:
Pusat pengajian Kejuruteraan Awam -
First presented to the public:
1/1/2020
Original Publication Date:
7/24/2020
Previously Published By:
Universiti Sains Malaysia
Place Of Publication:
School of Civil Engineering
Citation:
Extents:
Number of Pages - 213
License Grantor / Date Granted:
  / ( View License )
Date Deposited
2020-07-24 15:25:24.251
Submitter:
Mohamed Yunus Yusof

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Developing a prediction tool to improve the shading efficiency of the pedestrian zones / Wael A. Khudhayer1 2020-07-24 15:25:24.251