Analysis of the wind field characteristics induced by the 2019 Typhoon Bailu for the high-speed railway bridge crossing China’s southeast bay

Abstract There are a number of long-span bridges located in the southeast coastal bay of China which is prone to typhoons. Very limited studies have been made of the wind field characteristics in this bay which is special as it has various changes in fetch from sea to land and vice versa, depending on the wind direction. Thus, a detailed analysis of the wind properties of the 2019 Typhoon Bailu has been carried out and the findings are presented in this paper. The measurements were made from sensors on a 40 ​m-high meteorological mast in the vicinity of Quanzhou Bay Sea-Crossing High-Speed Railway Bridge. First, the characteristics of mean wind and turbulence are analyzed. The study results show that: the amplitude of the typhoon spectra after the second landfall is smaller than that before the landfall almost in one order of magnitude. The wind profile and turbulence coherence are also a focus of this study. It is revealed that a logarithmic model is more consistent with the measured wind speed profile compared with other commonly specified profiles. Strong coherence of u and w components at low frequencies is demonstrated in this study.