Aerodynamic and codification study of low-rise buildings: Part I – Fully elevated structures

Abstract

Elevated residential buildings are widely used in cyclone- and hurricane-prone coastal regions, such as Australia and the United States, as an effective solution to mitigate both storm surge damage and the impacts of extreme winds. The recent edition of ASCE 7–22 introduced wind design provisions for elevated structures for the first time, but these provisions remain under ongoing refinement. This study aims to assess the adequacy of the current ASCE 7–22 wind pressure coefficient provisions for elevated structures by conducting large-scale boundary layer wind tunnel tests at FIU's Wall of Wind Facility. The tests explored the aerodynamics of elevated buildings with varying heights and aspect ratios. Eight 1:10 scale gable-roof buildings were constructed based on post-hurricane damage reports, and peak pressure coefficients (${GC}_p$) were estimated for the floor, roof, and walls. These values were compared against the existing ASCE 7–22 provisions, revealing a significant underestimation of the external pressure coefficients. Based on the results, this study proposes increasing the ${GC}_p$ boundaries of specific zones by 50%–127% and introduces two new floor zones for more accurate estimation of wind pressure coefficients on elevated buildings. These findings have broad implications for improving the wind performance of elevated structures, particularly in cyclone- and hurricane-prone regions globally. It is envisioned that the results of this study, along with those in the companion paper, will be considered by the ASCE 7 Subcommittee on Wind Loads for potential inclusion in the next edition of ASCE 7–28, contributing to more resilient building designs.