Estimating Exposure Roughness Based on Google Earth
Publication: Journal of Structural Engineering
Volume 147, Issue 3
Abstract
Exposure roughness is significant in the evaluation of design wind loads. The roughness length () is a key parameter to determine the exposure coefficient. In current wind load provisions, is determined generally according to the exposure categories. However, subjective interpretation of upstream roughness by designers may lead to disagreements of exposure type. To address this issue, a more accurate method of determining the value of is proposed in this paper. This approach uses morphometric methods in combination with the application of Google Earth Pro or equivalent. A three-dimensional modeling methodology is proposed which is based on the two-dimensional images captured in Google Earth Pro. The city center of London, UK and Tampa International Airport, US are chosen as case studies to verify the accuracy of the proposed method by comparison with available measured data. The comparison shows that this method works well for the estimation of of upstream exposure.
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Data Availability Statement
Some or all data, models, or code that support the findings of this study are available from the corresponding author upon reasonable request.
Acknowledgments
The authors acknowledge the support received by the Natural Sciences and Engineering Research Council of Canada (NSERC) through a Discovery grant to the second author and the National Natural Science Foundation of China (Grant No. 51878580) to the third author. An earlier version of this paper was presented at the 15th International Conference on Wind Engineering in Beijing, China (September 1–5, 2019).
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Published In
Journal of Structural Engineering
Volume 147 • Issue 3 • March 2021
Copyright
© 2020 American Society of Civil Engineers.
History
Received: Mar 25, 2020
Accepted: Sep 10, 2020
Published online: Dec 24, 2020
Published in print: Mar 1, 2021
Discussion open until: May 24, 2021
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