Comparisons of Aerodynamic Data with the Main Wind Force–Resisting System Provisions of ASCE 7-16. I: Low-Rise Buildings

Abstract

This study assesses the wind load provisions for low-rise buildings with Chapters 27 and 28 in ASCE 7-16 and analyzes the dependence of the aerodynamics on the building geometric parameters. A systematic analysis of an aerodynamic database was used for this purpose. The mean and gust-factored uplift, base shear, and area-averaged wall pressure coefficients acting on the building surfaces comprise the main focus of this work. The results indicate that Chapter 27 captures the increasing tendency of roof uplift coefficients with larger roof heights reasonably well. The base shear obtained from the database is observed to vary with roof height, but conflicts with the design wind loads of ASCE 7-16. The ratio of roof height, H, to the horizontal plan dimension parallel to wind direction, L, is the critical nondimensional geometric parameter to model the uplift, leeward wall, and side wall pressure trends for low-rise buildings. It is also observed that the uplift can be used as a predictor of the side wall pressure coefficients for low-rise buildings. The Chapter 28 provisions conservatively envelop the data for relatively low buildings, but underestimate the wind loads for H/L>0.5.