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The complex dynamics of vertically separated flows pose a significant challenge when it comes to assessing the wind loads on multi-level structures, demanding a nuanced understanding of the intricate interplay between atmospheric conditions and architectural designs. Previous studies and wind loading standards provide insufficient guidance for designing wind pressures on multi-level buildings. The behavior of wind around perpendicularly attached surfaces is not quite similar to that of individual flat roofs or walls. When a body is composed of several surfaces with right or oblique angles, the separated flow from surfaces and their interactions will cause complex flow patterns around each surface. A wind tunnel experimental study was carried out on bluff bodies with attached flat plates and other adjacent bluff bodies with different heights to examine the wind-induced pressures on such complex shapes. Mean and peak pressure coefficients were measured to determine the flow interaction patterns and location of localized peak pressures. The results were compared to the Tokyo Polytechnic University Aerodynamic Database of isolated low-rise buildings without eaves. The research findings indicated that there was a noteworthy disparity between the minimum and maximum values and locations of peak pressures on both the wall and roof surfaces of the models used in this study, as compared to the results obtained by the Tokyo Polytechnic University. Moreover, the study conceivably pointed to the difference between the peak negative and positive pressure coefficient locations with the ASCE 7-22 wind loading zones. The peak suction zones were affected by the combined flows at perpendicular faces, and as a result, different wind load zones were obtained dissimilar to those introduced by ASCE 7-22. Wind loading standards may need to be modified to account for the wind pressures on complex building structures with an emphasis on the location of the peak negative pressure zones.
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1:100 Scaled Buildings with Perpendicular Surfaces:Subtitle
This dataset includes files from an extensive wind tunnel study of stepped-roof buildings conducted at the Wall of Wind facility at Florida International University. The aim of the study was to clarify the key factors that affect aerodynamic forces on complex architectural shapes. While ASCE7-22 offers a guideline for wind loads on building components and roofs, it falls short of providing the detailed data needed by engineers to calculate wind loads on the surfaces of stepped-roof buildings. This study fills that gap. The main subject under investigation was the impact of wind loads on different building geometries such as stepped roofs, U-shaped buildings, podium structures, and low-rise buildings with carport extensions. This involved a detailed examination of how various structural features influenced wind pressure distribution, with a specific emphasis on understanding the behavior of wind forces on these models. The outcomes include a series of detailed findings on wind pressure coefficients for each building model. These results offer insights into the wind load characteristics for different architectural forms, contributing to a better understanding of structural behavior under wind forces. The study findings will furnish additional data to enable engineers and scholars to more accurately assess and comprehend wind loads on buildings with multi-level roofs. The dataset includes diagrams of each model’s geometry and wind pressure data. The data highlighted key areas where wind pressures were most significant and how different building features either mitigated or exacerbated these pressures. The data gathered from this study can be reused in multiple ways. It can serve as a reference for designing wind-resilient buildings, particularly in regions susceptible to strong winds or hurricanes. The empirical data can also aid in validating and refining computational models for predicting wind loads on buildings. Additionally, it can be used in academic research for further exploration into wind engineering, urban planning, and architectural design, potentially leading to innovations in building safety standards and construction practices.
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- Award ID(s):
- 1841503
- PAR ID:
- 10569972
- Publisher / Repository:
- Designsafe-CI
- Date Published:
- Subject(s) / Keyword(s):
- peak negative pressure coefficients peak positive pressure coefficients
- Format(s):
- Medium: X
- Institution:
- Wall of Wind - Florida International University
- Sponsoring Org:
- National Science Foundation
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