Effect of time-variant structural modal parameters on accurate estimation of wind-induced dynamic responses of high-rise buildings during typhoons

Abstract

Structural modal parameters of high-rise buildings during severe winds generally exhibit time-variant features, which conflicts with the assumption adopted in the wind-resistant design procedure that the modal parameters are time-invariant values. This may lead to inaccurate estimation of wind-induced structural dynamic responses, thus deteriorating the reliability of structural design of high-rise buildings. To address this issue, this paper first evaluates the time-variant modal parameters of a 600-m-high skyscraper based on building accelerations measured during Super Typhoon Mangkhut. Then, the identified time-variant modal parameters are combined with the wind loads estimated from wind tunnel test on a 1:500 scaled model of the skyscraper to reproduce the typhoon-induced building accelerations. The results show that the reproduced accelerations based on the time-variant modal parameters agree well with the field-measured ones. Moreover, a comparative study between adoption of the time-variant modal parameters and time-invariant modal parameters is conducted, which shows that the former case provides more accurate estimation of the building dynamic responses during the extreme typhoon event. This paper aims to explore an effective means for precise evaluation of typhoon-induced dynamic responses of high-rise buildings.