| Summary: | 碩士 === 淡江大學 === 土木工程學系 === 91 === For slender high-rise buildings, flexible and dynamically sensitive, wind effects are likely to be the dominant factor on buildings’ lateral design loading. Decreasing fundamental frequency, flexible structure resonated with wind field that surrounded the building, and resulted stronger wind load. It’s necessary for structural engineering to evaluate the proper design wind load.
This research project performs in-depth study on several national wind codes among them are Taiwan, United States （ANSI）, Japan（AIJ）, Canada（NBC）and Australia（SAA）. All these wind codes have some variations on the articles regarding alongwind, acrosswind and torsional wind loads. Alongwind design wind load is mainly caused by incident turbulence in the approaching wind. The primary affecting parameters include: basic wind speed, terrain subcategories, wind speed profile, wind force coefficient, wind force spectrum, gust wind factor and alongwind load formula. Acrosswind design wind load is mainly induced by vortex shedding in the wake of building. The primary affecting parameters include: acrosswind force spectrum and Acrosswind load formula. Torsional design wind load is mainly generated by asymmetric wind pressure distribution on building surface. The calculation proceedure is similar to the acrosswind design loads.
As for the wind loads combination, there are several existing models, such as scalar combination, elliptical combination and polygon combination, to be taken into consioderation. The primary difference among those models is the degree of correlation between along and across wind load.
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