Spatiotemporal variation in air density and associated effects on the wind-induced response of high-rise buildings

Abstract

It is widely acknowledged that the density of the atmosphere noticeably varies with space and time. However, the effects of spatiotemporal variation in air density on the wind-induced response of building structures, especially of high-rise buildings, have usually been neglected in practice. This paper presents a field study on the spatiotemporal variation in air density based on meteorological records collected from weather stations at various latitudes and ground elevations. The vertical profile of air density in a typhoon’s core region is highlighted, and a data-driven profile model is proposed. The dependence of wind-induced response of high-rise buildings on air density is then investigated via a wind tunnel test. A pressure model for a high-rise building with a square cross-section is tested, and the wind-induced acceleration response of the building is estimated. The results suggest that if the proposed profile of the typhoon air density is adopted, the estimation of the wind-induced structural response would be below the permitted level, while if a scheme with a constant air density is adopted, the structural response would exceed the limit. This means that taking the spatiotemporal variation in air density into account in wind-resistant building design can sometimes lead to considerable economic benefits.