Wind Loading on Tall Building Structures in Consideration of Performance-Based Design

摘要

Tall buildings are vulnerable to wind loading, and their designs are therefore frequently governed by wind loads. In buildings' wind design, attempts have been made to apply performance-based design (PBD) in result of its potential advantages to buildings' seismic design. This paper addresses basic issues in applying PBD to tall building wind design, which were raised by investigating different characteristics between wind loading and seismic loading. The main differences lie in (ⅰ) probabilistic distribution of winds and ground accelerations, and (ⅱ) aerodynamic effects such as vortex-shedding. Potential benefits of performance-based wind design were investigated by comparing wind loads with seismic loads for various return periods. In order to derive general discussions and conclusions, the study was applied to a generic tall building with a square plan dimension of 30 m by 30 m, and a building height of 300 m, leaving aspect ratio (slenderness ratio) often (10). The across-wind and along-wind loads and their responses were simulated for a range of return periods, covering service level, strength level, and collapse-prevention level events. Findings concluded that the "heavy-headed, light-tailed" probabilistic distribution of wind speeds, and building aerodynamic characteristics which generate high loads in service level winds, demerit the application of PBD to tall building wind design.