Wind‐induced inter‐story drift analysis and equivalent static wind load for multiple targets of tall buildings

Abstract

SUMMARYIn super high-rise buildings with varying story heights, the wind-induced inter-story drifts might violate the specified limit. However, these effects have seldom been concerned in wind-induced response analysis. The theory and application of equivalent static wind load (ESWL) for wind-induced inter-story drifts of super high-rise buildings were studied in this paper. A spectral decomposition method suitable for multi-point excitation problems was firstly proposed. The formula of ESWL targeting for largest inter-story drift was derived. For more reasonable structural design, the ESWL for multiple targets including displacement atop of building and inter-story drifts at all story levels is put forward, in which the dominant modal inertial forces are adopted as the based load vectors. The presented methods were finally verified by its application for the wind-induced response analysis for a tallest super tall building in Guangzhou. The researched results showed that the proposed spectral decomposition method not only has the same precision as the complete quadratic combination method but also possesses higher computation efficiency. The ESWL for multiple targets produces the same static responses for all the specified wind-induced response, so it is much more rational for wind-resistant structural design. Meanwhile, it is more reasonable to select the wind-induced responses in the same direction simultaneously as the targeted values for obtaining the required ESWLs; however, the ESWL targeting for the wind-induced responses in all degrees of freedom would generate more queer and unrealistic ESWLs distribution.

Lateral drift constrained structural optimization of an actual supertall building acted by wind load

“…Apparently, the ESWL in this study should be multiple oriented, whereas the commonly used ESWL computational method usually takes the top‐level displacement as the equivalent target. By referencing the study of Fu, Katsumura, the multiple‐oriented ESWL will be computed through the following procedure.…”

“… where n is the number of stories of the building. Because { y } and can be easily computed by the complete quadratic combination method or its evolutionary form, the coefficient vector { X } can be obtained by solving the equations consisting of Equations and . In general, the dimension of vector { X } is smaller than the equivalent targets, meaning that the number of unknowns is smaller than the number of equations, and consequently, there is no way of finding an exact solution to these equations.…”

“…where n is the number of stories of the building. Because {y} and b y f g can be easily computed by the complete quadratic combination method or its evolutionary form, [24] the coefficient vector {X} can be obtained by solving the equations consisting of Equations 9 and 10.…”