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This paper investigates the impact of Super Typhoon Mangkhut on Hong Kong, especially the wind effects on high-rise buildings, based on 24-h-long field measurement records collected from the two tallest skyscrapers (484 and 420 m in height) in the metropolis and six meteorological stations on different types of terrain on September 16, 2018. Mangkhut corresponded to a 50-year return period and was the most violent typhoon since wind records in Hong Kong began in 1946. In this large-scale monitoring study, the wind characteristics of Mangkhut over different terrains are investigated using the climate records by anemometers and a weather surveillance radar, the wind-excited structural responses of the monitored skyscrapers are analyzed according to measurements by accelerometers and a global navigation satellite system, the structural dynamic properties are estimated by the random decrement technique and the Bayesian spectral density approach, and both rigid and aeroelastic modeling techniques for wind tunnel testing are validated by in-situ measurements during the typhoon. This study aims to enhance the understanding of strong typhoon-generated wind characteristics over different terrains and provide comprehensive information for the wind-resistant design of high-rise buildings in tropical cyclone-prone regions. [ABSTRACT FROM AUTHOR]

This paper presents work on validating the dynamic wind load predicted by a wind tunnel model with the values identified from full-scale field vibration data of a super-tall building in Hong Kong. Dynamic wind load in this work refers to the power spectral density (PSD) of the modal force near the natural frequency of a particular mode of the building, in the context of random vibration with stationary loading and response. This quantity reflects the turbulence characteristics integrated over the building body and is of importance in wind engineering design. This study presents a method to predict the modal PSD of wind load of the first two translational modes of a tall building. The method combines wind tunnel test information and mean wind data available in the free field; the latter taken to be at the Waglan Island station maintained by the Hong Kong Observatory. On the full-scale side, although the modal PSD is not directly observable, it is identified from field vibration data measured at the building top during strong wind events. A Bayesian modal identification method is used for determining the most probable value and the uncertainty of the modal parameters including the natural frequency, damping ratio, and the modal PSD. A number of recent strong wind events are analyzed. Reasonable agreement is observed between the wind tunnel model predictions and the values identified from field data. Factors that can potentially lead to discrepancy are discussed. As the same random vibration modeling consistent with conventional wind engineering design has been used in the wind tunnel prediction model and field identification model, the results are directly transferable among these three disciplines. [ABSTRACT FROM AUTHOR]