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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]

Typhoon winds near the external eye wall of a strong typhoon are extremely nonstationary and disastrous due to its vortex and convective origin as well as its high wind speeds. However, typhoon-induced nonstationary responses of long-span bridges are currently analyzed with the assumption of time-invariant wind coherence. By taking the Stonecutters cable-stayed bridge in Hong Kong under Typhoon Hato in 2017 as an example, this paper presents the time-varying wind spectra and coherences for the bridge based on the wind data recorded by the multiple anemometers installed on the bridge. The analytical framework for nonstationary buffeting analysis of long-span bridges under typhoon winds is enhanced by considering time-varying wind coherence and applied to the Stonecutters Bridge under Typhoon Hato. The computed responses are compared with the field measurement responses. The comparative results demonstrate the feasibility and accuracy of the enhanced framework for buffeting analysis of long-span bridges with time-varying wind spectra and coherences. Comparative results with the other two cases of time-invariant coherence functions also highlight the importance and necessity of considering the time-varying wind coherence in the nonstationary buffeting analysis of long-span bridges under typhoon winds. [ABSTRACT FROM AUTHOR]